Суббота, 9 июня 2018, 18:15 +03:00 от Vladislav Shpilevoy <v.shpilevoy@tarantool.org>:

Thanks for the patch! I have pushed a separate commit with my fixes, but
it does not pass the test. Please, fix it.

And use unit.h helpers: ok, isnt, is, fail etc to test something instead
of assertions. Assert is omitted in Release build, and the test will test
nothing.
Done.


On 09/06/2018 17:40, imeevma@tarantool.org wrote:
> Due to limitation of reference counters for tuple being only
> 65535 it was possible to reach this limitation. This patch
> increases capacity of reference counters to 4 billions.
>
> Closes #3224
> ---
> Branch: https://github.com/tarantool/tarantool/commits/imeevma/gh-3224-tuple-bigrefs
> Issue: https://github.com/tarantool/tarantool/issues/3224
>
> src/box/box.cc | 20 +++---
> src/box/errcode.h | 2 +-
> src/box/index.cc | 20 +++---
> src/box/lua/tuple.c | 5 +-
> src/box/port.c | 8 +--
> src/box/tuple.c | 143 ++++++++++++++++++++++++++++++++++++++++--
> src/box/tuple.h | 105 ++++++++++++-------------------
> src/box/vinyl.c | 38 +++++------
> test/box/misc.result | 39 ++++++------
> test/box/select.result | 43 +++++++++++--
> test/box/select.test.lua | 21 +++++--
> test/unit/CMakeLists.txt | 3 +
> test/unit/tuple_bigref.c | 117 ++++++++++++++++++++++++++++++++++
> test/unit/tuple_bigref.result | 5 ++
> 14 files changed, 413 insertions(+), 156 deletions(-)
> create mode 100644 test/unit/tuple_bigref.c
> create mode 100644 test/unit/tuple_bigref.result
>
> diff --git a/src/box/box.cc b/src/box/box.cc
> index c728a4c..4257861 100644
> --- a/src/box/box.cc
> +++ b/src/box/box.cc
> @@ -174,20 +174,22 @@ process_rw(struct request *request, struct space *space, struct tuple **result)
> txn_rollback_stmt();
> return -1;
> }
> + if (result == NULL)
> + return txn_commit_stmt(txn, request);
> + *result = tuple;
> + if (tuple == NULL)
> + return txn_commit_stmt(txn, request);
> /*
> * Pin the tuple locally before the commit,
> * otherwise it may go away during yield in
> * when WAL is written in autocommit mode.
> */
> - TupleRefNil ref(tuple);
> - if (txn_commit_stmt(txn, request) != 0)
> - return -1;
> - if (result != NULL) {
> - if (tuple != NULL && tuple_bless(tuple) == NULL)
> - return -1;
> - *result = tuple;
> - }
> - return 0;
> + tuple_ref(tuple);
> + int rc = txn_commit_stmt(txn, request);
> + if (rc == 0)
> + tuple_bless(tuple);
> + tuple_unref(tuple);
> + return rc;
> }
>
> void
> diff --git a/src/box/errcode.h b/src/box/errcode.h
> index a0759f8..e009524 100644
> --- a/src/box/errcode.h
> +++ b/src/box/errcode.h
> @@ -138,7 +138,7 @@ struct errcode_record {
> /* 83 */_(ER_ROLE_EXISTS, "Role '%s' already exists") \
> /* 84 */_(ER_CREATE_ROLE, "Failed to create role '%s': %s") \
> /* 85 */_(ER_INDEX_EXISTS, "Index '%s' already exists") \
> - /* 86 */_(ER_TUPLE_REF_OVERFLOW, "Tuple reference counter overflow") \
> + /* 86 */_(ER_UNUSED6, "") \
> /* 87 */_(ER_ROLE_LOOP, "Granting role '%s' to role '%s' would create a loop") \
> /* 88 */_(ER_GRANT, "Incorrect grant arguments: %s") \
> /* 89 */_(ER_PRIV_GRANTED, "User '%s' already has %s access on %s '%s'") \
> diff --git a/src/box/index.cc b/src/box/index.cc
> index 3c62ec1..f992bc9 100644
> --- a/src/box/index.cc
> +++ b/src/box/index.cc
> @@ -220,8 +220,8 @@ box_index_random(uint32_t space_id, uint32_t index_id, uint32_t rnd,
> /* No tx management, random() is for approximation anyway. */
> if (index_random(index, rnd, result) != 0)
> return -1;
> - if (*result != NULL && tuple_bless(*result) == NULL)
> - return -1;
> + if (*result != NULL)
> + tuple_bless(*result);
> return 0;
> }
>
> @@ -253,8 +253,8 @@ box_index_get(uint32_t space_id, uint32_t index_id, const char *key,
> txn_commit_ro_stmt(txn);
> /* Count statistics. */
> rmean_collect(rmean_box, IPROTO_SELECT, 1);
> - if (*result != NULL && tuple_bless(*result) == NULL)
> - return -1;
> + if (*result != NULL)
> + tuple_bless(*result);
> return 0;
> }
>
> @@ -285,8 +285,8 @@ box_index_min(uint32_t space_id, uint32_t index_id, const char *key,
> return -1;
> }
> txn_commit_ro_stmt(txn);
> - if (*result != NULL && tuple_bless(*result) == NULL)
> - return -1;
> + if (*result != NULL)
> + tuple_bless(*result);
> return 0;
> }
>
> @@ -317,8 +317,8 @@ box_index_max(uint32_t space_id, uint32_t index_id, const char *key,
> return -1;
> }
> txn_commit_ro_stmt(txn);
> - if (*result != NULL && tuple_bless(*result) == NULL)
> - return -1;
> + if (*result != NULL)
> + tuple_bless(*result);
> return 0;
> }
>
> @@ -397,8 +397,8 @@ box_iterator_next(box_iterator_t *itr, box_tuple_t **result)
> assert(result != NULL);
> if (iterator_next(itr, result) != 0)
> return -1;
> - if (*result != NULL && tuple_bless(*result) == NULL)
> - return -1;
> + if (*result != NULL)
> + tuple_bless(*result);
> return 0;
> }
>
> diff --git a/src/box/lua/tuple.c b/src/box/lua/tuple.c
> index 8057331..22fe696 100644
> --- a/src/box/lua/tuple.c
> +++ b/src/box/lua/tuple.c
> @@ -496,10 +496,7 @@ luaT_pushtuple(struct lua_State *L, box_tuple_t *tuple)
> luaL_pushcdata(L, CTID_CONST_STRUCT_TUPLE_REF);
> *ptr = tuple;
> /* The order is important - first reference tuple, next set gc */
> - if (box_tuple_ref(tuple) != 0) {
> - luaT_error(L);
> - return;
> - }
> + box_tuple_ref(tuple);
> lua_pushcfunction(L, lbox_tuple_gc);
> luaL_setcdatagc(L, -2);
> }
> diff --git a/src/box/port.c b/src/box/port.c
> index 03f6be7..9b6b858 100644
> --- a/src/box/port.c
> +++ b/src/box/port.c
> @@ -45,8 +45,7 @@ port_tuple_add(struct port *base, struct tuple *tuple)
> struct port_tuple *port = port_tuple(base);
> struct port_tuple_entry *e;
> if (port->size == 0) {
> - if (tuple_ref(tuple) != 0)
> - return -1;
> + tuple_ref(tuple);
> e = &port->first_entry;
> port->first = port->last = e;
> } else {
> @@ -55,10 +54,7 @@ port_tuple_add(struct port *base, struct tuple *tuple)
> diag_set(OutOfMemory, sizeof(*e), "mempool_alloc", "e");
> return -1;
> }
> - if (tuple_ref(tuple) != 0) {
> - mempool_free(&port_tuple_entry_pool, e);
> - return -1;
> - }
> + tuple_ref(tuple);
> port->last->next = e;
> port->last = e;
> }
> diff --git a/src/box/tuple.c b/src/box/tuple.c
> index 014f374..b632183 100644
> --- a/src/box/tuple.c
> +++ b/src/box/tuple.c
> @@ -48,6 +48,28 @@ enum {
> OBJSIZE_MIN = 16,
> };
>
> +/**
> + * Container for big reference counters. Contains array of big
> + * reference counters, size of this array and number of non-zero
> + * big reference counters. When reference counter of tuple becomes
> + * more than 32767, field refs of this tuple becomes index of big
> + * reference counter in big reference counter array and field
> + * is_bigref is set true. The moment big reference becomes equal
> + * 32767 it is set to 0, refs of the tuple becomes 32767 and
> + * is_bigref becomes false. Big reference counter can be equal to
> + * 0 or be more than 32767.
> + */
> +static struct bigref_list {
> + /** Array of big reference counters. */
> + uint32_t *refs;
> + /** Number of non-zero elements in the array. */
> + uint16_t size;
> + /** Capacity of the array. */
> + uint16_t capacity;
> + /** Index of first free element. */
> + uint16_t vacant_index;
> +} bigref_list;
> +
> static const double ALLOC_FACTOR = 1.05;
>
> /**
> @@ -151,6 +173,13 @@ tuple_validate_raw(struct tuple_format *format, const char *tuple)
> return 0;
> }
>
> +/** Initialize big references container. */
> +static inline void
> +bigref_list_create()
> +{
> + memset(&bigref_list, 0, sizeof(bigref_list));
> +}
> +
> /**
> * Incremented on every snapshot and is used to distinguish tuples
> * which were created after start of a snapshot (these tuples can
> @@ -211,6 +240,8 @@ tuple_init(field_name_hash_f hash)
>
> box_tuple_last = NULL;
>
> + bigref_list_create();
> +
> if (coll_id_cache_init() != 0)
> return -1;
>
> @@ -244,6 +275,107 @@ tuple_arena_create(struct slab_arena *arena, struct quota *quota,
> }
> }
>
> +enum {
> + BIGREF_FACTOR = 2,
> + BIGREF_MAX = UINT32_MAX,
> + BIGREF_MIN_CAPACITY = 16,
> + /**
> + * Only 15 bits are available for bigref list index in
> + * struct tuple.
> + */
> + BIGREF_MAX_CAPACITY = UINT16_MAX >> 1
> +};
> +
> +/** Destroy big references and free memory that was allocated. */
> +static inline void
> +bigref_list_reset()
> +{
> + free(bigref_list.refs);
> + bigref_list_create();
> +}
> +
> +/**
> + * Increase capacity of bigref_list.
> + */
> +static inline void
> +bigref_list_increase_capacity()
> +{
> + assert(bigref_list.capacity == bigref_list.vacant_index);
> + uint32_t *refs = bigref_list.refs;
> + uint16_t capacity = bigref_list.capacity;
> + if (capacity == 0)
> + capacity = BIGREF_MIN_CAPACITY;
> + else if (capacity < BIGREF_MAX_CAPACITY)
> + capacity = MIN(capacity * BIGREF_FACTOR, BIGREF_MAX_CAPACITY);
> + else
> + panic("Too many big references");
> + refs = (uint32_t *) realloc(refs, capacity * sizeof(*refs));
> + if (refs == NULL) {
> + panic("failed to reallocate %zu bytes: Cannot allocate "\
> + "memory.", capacity * sizeof(*refs));
> + }
> + for(uint16_t i = bigref_list.capacity; i < capacity; ++i) {
> + refs[i] = i + 1;
> + }
> + bigref_list.refs = refs;
> + bigref_list.capacity = capacity;
> +}
> +
> +/**
> + * Return index for new big reference counter and allocate memory
> + * if needed.
> + * @retval index for new big reference counter.
> + */
> +static inline uint16_t
> +bigref_list_new_index()
> +{
> + if (bigref_list.size == bigref_list.capacity)
> + bigref_list_increase_capacity();
> + ++bigref_list.size;
> + uint16_t vacant_index = bigref_list.vacant_index;
> + bigref_list.vacant_index = bigref_list.refs[vacant_index];
> + return vacant_index;
> +}
> +
> +void
> +tuple_ref_slow(struct tuple *tuple)
> +{
> + assert(tuple->is_bigref || tuple->refs == TUPLE_REF_MAX);
> + if (! tuple->is_bigref) {
> + tuple->ref_index = bigref_list_new_index();
> + tuple->is_bigref = true;
> + bigref_list.refs[tuple->ref_index] = TUPLE_REF_MAX;
> + } else if (bigref_list.refs[tuple->ref_index] == BIGREF_MAX) {
> + panic("Tuple big reference counter overflow");
> + }
> + bigref_list.refs[tuple->ref_index]++;
> +}
> +
> +/**
> + * Free index and add it to free-index-list. Free memory
> + * when size == 0.
> + */
> +static inline void
> +bigref_list_delete_index(uint16_t index)
> +{
> + bigref_list.refs[index] = bigref_list.vacant_index;
> + bigref_list.vacant_index = index;
> + if (--bigref_list.size == 0)
> + bigref_list_reset();
> +}
> +
> +void
> +tuple_unref_slow(struct tuple *tuple)
> +{
> + assert(tuple->is_bigref &&
> + bigref_list.refs[tuple->ref_index] > TUPLE_REF_MAX);
> + if(--bigref_list.refs[tuple->ref_index] == TUPLE_REF_MAX) {
> + bigref_list_delete_index(tuple->ref_index);
> + tuple->ref_index = TUPLE_REF_MAX;
> + tuple->is_bigref = false;
> + }
> +}
> +
> void
> tuple_arena_destroy(struct slab_arena *arena)
> {
> @@ -265,6 +397,8 @@ tuple_free(void)
> tuple_format_free();
>
> coll_id_cache_destroy();
> +
> + bigref_list_reset();
> }
>
> box_tuple_format_t *
> @@ -288,7 +422,8 @@ int
> box_tuple_ref(box_tuple_t *tuple)
> {
> assert(tuple != NULL);
> - return tuple_ref(tuple);
> + tuple_ref(tuple);
> + return 0;
> }
>
> void
> @@ -357,10 +492,7 @@ box_tuple_iterator(box_tuple_t *tuple)
> "mempool", "new slab");
> return NULL;
> }
> - if (tuple_ref(tuple) != 0) {
> - mempool_free(&tuple_iterator_pool, it);
> - return NULL;
> - }
> + tuple_ref(tuple);
> tuple_rewind(it, tuple);
> return it;
> }
> @@ -451,7 +583,6 @@ box_tuple_new(box_tuple_format_t *format, const char *data, const char *end)
> struct tuple *ret = tuple_new(format, data, end);
> if (ret == NULL)
> return NULL;
> - /* Can't fail on zero refs. */
> return tuple_bless(ret);
> }
>
> diff --git a/src/box/tuple.h b/src/box/tuple.h
> index e2384dd..14dbd40 100644
> --- a/src/box/tuple.h
> +++ b/src/box/tuple.h
> @@ -105,8 +105,7 @@ typedef struct tuple box_tuple_t;
> * tuple will leak.
> *
> * \param tuple a tuple
> - * \retval -1 on error (check box_error_last())
> - * \retval 0 on success
> + * \retval 0 always
> * \sa box_tuple_unref()
> */
> int
> @@ -269,8 +268,7 @@ box_tuple_next(box_tuple_iterator_t *it);
> * Use box_tuple_format_default() to create space-independent tuple.
> * \param data tuple data in MsgPack Array format ([field1, field2, ...]).
> * \param end the end of \a data
> - * \retval NULL on out of memory
> - * \retval tuple otherwise
> + * \retval tuple
> * \pre data, end is valid MsgPack Array
> * \sa \code box.tuple.new(data) \endcode
> */
> @@ -307,9 +305,17 @@ box_tuple_upsert(const box_tuple_t *tuple, const char *expr, const
> */
> struct PACKED tuple
> {
> - /** reference counter */
> - uint16_t refs;
> - /** format identifier */
> + union {
> + /** Reference counter. */
> + uint16_t refs;
> + struct {
> + /** Index of big reference counter. */
> + uint16_t ref_index : 15;
> + /** Big reference flag. */
> + bool is_bigref : 1;
> + };
> + };
> + /** Format identifier. */
> uint16_t format_id;
> /**
> * Length of the MessagePack data in raw part of the
> @@ -774,26 +780,36 @@ tuple_field_uuid(const struct tuple *tuple, int fieldno,
> return 0;
> }
>
> -enum { TUPLE_REF_MAX = UINT16_MAX };
> +enum { TUPLE_REF_MAX = UINT16_MAX >> 1 };
> +
> +/**
> + * Increase tuple big reference counter.
> + * @param tuple Tuple to reference.
> + */
> +void
> +tuple_ref_slow(struct tuple *tuple);
>
> /**
> * Increment tuple reference counter.
> * @param tuple Tuple to reference.
> - * @retval 0 Success.
> - * @retval -1 Too many refs error.
> */
> -static inline int
> +static inline void
> tuple_ref(struct tuple *tuple)
> {
> - if (tuple->refs + 1 > TUPLE_REF_MAX) {
> - diag_set(ClientError, ER_TUPLE_REF_OVERFLOW);
> - return -1;
> - }
> - tuple->refs++;
> - return 0;
> + if (unlikely(tuple->refs >= TUPLE_REF_MAX))
> + tuple_ref_slow(tuple);
> + else
> + tuple->refs++;
> }
>
> /**
> + * Decrease tuple big reference counter.
> + * @param tuple Tuple to reference.
> + */
> +void
> +tuple_unref_slow(struct tuple *tuple);
> +
> +/**
> * Decrement tuple reference counter. If it has reached zero, free the tuple.
> *
> * @pre tuple->refs + count >= 0
> @@ -802,10 +818,9 @@ static inline void
> tuple_unref(struct tuple *tuple)
> {
> assert(tuple->refs - 1 >= 0);
> -
> - tuple->refs--;
> -
> - if (tuple->refs == 0)
> + if (unlikely(tuple->is_bigref))
> + tuple_unref_slow(tuple);
> + else if (--tuple->refs == 0)
> tuple_delete(tuple);
> }
>
> @@ -813,25 +828,18 @@ extern struct tuple *box_tuple_last;
>
> /**
> * Convert internal `struct tuple` to public `box_tuple_t`.
> - * \retval tuple on success
> - * \retval NULL on error, check diag
> + * \retval tuple
> * \post \a tuple ref counted until the next call.
> - * \post tuple_ref() doesn't fail at least once
> * \sa tuple_ref
> */
> static inline box_tuple_t *
> tuple_bless(struct tuple *tuple)
> {
> assert(tuple != NULL);
> - /* Ensure tuple can be referenced at least once after return */
> - if (tuple->refs + 2 > TUPLE_REF_MAX) {
> - diag_set(ClientError, ER_TUPLE_REF_OVERFLOW);
> - return NULL;
> - }
> - tuple->refs++;
> + tuple_ref(tuple);
> /* Remove previous tuple */
> if (likely(box_tuple_last != NULL))
> - tuple_unref(box_tuple_last); /* do not throw */
> + tuple_unref(box_tuple_last);
> /* Remember current tuple */
> box_tuple_last = tuple;
> return tuple;
> @@ -849,41 +857,6 @@ tuple_to_buf(const struct tuple *tuple, char *buf, size_t size);
> #include "tuple_update.h"
> #include "errinj.h"
>
> -/**
> - * \copydoc tuple_ref()
> - * \throws if overflow detected.
> - */
> -static inline void
> -tuple_ref_xc(struct tuple *tuple)
> -{
> - if (tuple_ref(tuple))
> - diag_raise();
> -}
> -
> -/**
> - * \copydoc tuple_bless
> - * \throw ER_TUPLE_REF_OVERFLOW
> - */
> -static inline box_tuple_t *
> -tuple_bless_xc(struct tuple *tuple)
> -{
> - box_tuple_t *blessed = tuple_bless(tuple);
> - if (blessed == NULL)
> - diag_raise();
> - return blessed;
> -}
> -
> -/** Make tuple references exception-friendly in absence of @finally. */
> -struct TupleRefNil {
> - struct tuple *tuple;
> - TupleRefNil (struct tuple *arg) :tuple(arg)
> - { if (tuple) tuple_ref_xc(tuple); }
> - ~TupleRefNil() { if (tuple) tuple_unref(tuple); }
> -
> - TupleRefNil(const TupleRefNil&) = delete;
> - void operator=(const TupleRefNil&) = delete;
> -};
> -
> /* @copydoc tuple_field_with_type() */
> static inline const char *
> tuple_field_with_type_xc(const struct tuple *tuple, uint32_t fieldno,
> diff --git a/src/box/vinyl.c b/src/box/vinyl.c
> index f0d2687..dc0d020 100644
> --- a/src/box/vinyl.c
> +++ b/src/box/vinyl.c
> @@ -3822,7 +3822,6 @@ vinyl_iterator_primary_next(struct iterator *base, struct tuple **ret)
> assert(base->next = vinyl_iterator_primary_next);
> struct vinyl_iterator *it = (struct vinyl_iterator *)base;
> assert(it->lsm->index_id == 0);
> - struct tuple *tuple;
>
> if (it->tx == NULL) {
> diag_set(ClientError, ER_CURSOR_NO_TRANSACTION);
> @@ -3833,18 +3832,15 @@ vinyl_iterator_primary_next(struct iterator *base, struct tuple **ret)
> goto fail;
> }
>
> - if (vy_read_iterator_next(&it->iterator, &tuple) != 0)
> + if (vy_read_iterator_next(&it->iterator, ret) != 0)
> goto fail;
> -
> - if (tuple == NULL) {
> + if (*ret == NULL) {
> /* EOF. Close the iterator immediately. */
> vinyl_iterator_close(it);
> - *ret = NULL;
> - return 0;
> + } else {
> + tuple_bless(*ret);
> }
> - *ret = tuple_bless(tuple);
> - if (*ret != NULL)
> - return 0;
> + return 0;
> fail:
> vinyl_iterator_close(it);
> return -1;
> @@ -3890,11 +3886,10 @@ next:
> * Note, there's no need in vy_tx_track() as the
> * tuple is already tracked in the secondary index.
> */
> - struct tuple *full_tuple;
> if (vy_point_lookup(it->lsm->pk, it->tx, vy_tx_read_view(it->tx),
> - tuple, &full_tuple) != 0)
> + tuple, ret) != 0)
> goto fail;
> - if (full_tuple == NULL) {
> + if (*ret == NULL) {
> /*
> * All indexes of a space must be consistent, i.e.
> * if a tuple is present in one index, it must be
> @@ -3908,10 +3903,9 @@ next:
> vy_lsm_name(it->lsm), vy_stmt_str(tuple));
> goto next;
> }
> - *ret = tuple_bless(full_tuple);
> - tuple_unref(full_tuple);
> - if (*ret != NULL)
> - return 0;
> + tuple_bless(*ret);
> + tuple_unref(*ret);
> + return 0;
> fail:
> vinyl_iterator_close(it);
> return -1;
> @@ -3997,16 +3991,12 @@ vinyl_index_get(struct index *index, const char *key,
> const struct vy_read_view **rv = (tx != NULL ? vy_tx_read_view(tx) :
> &env->xm->p_global_read_view);
>
> - struct tuple *tuple;
> - if (vy_lsm_full_by_key(lsm, tx, rv, key, part_count, &tuple) != 0)
> + if (vy_lsm_full_by_key(lsm, tx, rv, key, part_count, ret) != 0)
> return -1;
> -
> - if (tuple != NULL) {
> - *ret = tuple_bless(tuple);
> - tuple_unref(tuple);
> - return *ret == NULL ? -1 : 0;
> + if (*ret != NULL) {
> + tuple_bless(*ret);
> + tuple_unref(*ret);
> }
> - *ret = NULL;
> return 0;
> }
>
> diff --git a/test/box/misc.result b/test/box/misc.result
> index 8f94f55..f7703ba 100644
> --- a/test/box/misc.result
> +++ b/test/box/misc.result
> @@ -332,7 +332,6 @@ t;
> - 'box.error.UNKNOWN_UPDATE_OP : 28'
> - 'box.error.WRONG_COLLATION_OPTIONS : 151'
> - 'box.error.CURSOR_NO_TRANSACTION : 80'
> - - 'box.error.TUPLE_REF_OVERFLOW : 86'
> - 'box.error.ALTER_SEQUENCE : 143'
> - 'box.error.INVALID_XLOG_NAME : 75'
> - 'box.error.SAVEPOINT_EMPTY_TX : 60'
> @@ -360,7 +359,7 @@ t;
> - 'box.error.VINYL_MAX_TUPLE_SIZE : 139'
> - 'box.error.LOAD_FUNCTION : 99'
> - 'box.error.INVALID_XLOG : 74'
> - - 'box.error.PRIV_NOT_GRANTED : 91'
> + - 'box.error.READ_VIEW_ABORTED : 130'
> - 'box.error.TRANSACTION_CONFLICT : 97'
> - 'box.error.GUEST_USER_PASSWORD : 96'
> - 'box.error.PROC_C : 102'
> @@ -405,7 +404,7 @@ t;
> - 'box.error.injection : table: <address>
> - 'box.error.NULLABLE_MISMATCH : 153'
> - 'box.error.LAST_DROP : 15'
> - - 'box.error.NO_SUCH_ROLE : 82'
> + - 'box.error.TUPLE_FORMAT_LIMIT : 16'
> - 'box.error.DECOMPRESSION : 124'
> - 'box.error.CREATE_SEQUENCE : 142'
> - 'box.error.CREATE_USER : 43'
> @@ -414,66 +413,66 @@ t;
> - 'box.error.SEQUENCE_OVERFLOW : 147'
> - 'box.error.SYSTEM : 115'
> - 'box.error.KEY_PART_IS_TOO_LONG : 118'
> - - 'box.error.TUPLE_FORMAT_LIMIT : 16'
> - - 'box.error.BEFORE_REPLACE_RET : 53'
> + - 'box.error.INJECTION : 8'
> + - 'box.error.INVALID_MSGPACK : 20'
> - 'box.error.NO_SUCH_SAVEPOINT : 61'
> - 'box.error.TRUNCATE_SYSTEM_SPACE : 137'
> - 'box.error.VY_QUOTA_TIMEOUT : 135'
> - 'box.error.WRONG_INDEX_OPTIONS : 108'
> - 'box.error.INVALID_VYLOG_FILE : 133'
> - 'box.error.INDEX_FIELD_COUNT_LIMIT : 127'
> - - 'box.error.READ_VIEW_ABORTED : 130'
> + - 'box.error.PRIV_NOT_GRANTED : 91'
> - 'box.error.USER_MAX : 56'
> - - 'box.error.PROTOCOL : 104'
> + - 'box.error.BEFORE_REPLACE_RET : 53'
> - 'box.error.TUPLE_NOT_ARRAY : 22'
> - 'box.error.KEY_PART_COUNT : 31'
> - 'box.error.ALTER_SPACE : 12'
> - 'box.error.ACTIVE_TRANSACTION : 79'
> - 'box.error.EXACT_FIELD_COUNT : 38'
> - 'box.error.DROP_SEQUENCE : 144'
> - - 'box.error.INVALID_MSGPACK : 20'
> - 'box.error.MORE_THAN_ONE_TUPLE : 41'
> - - 'box.error.RTREE_RECT : 101'
> - - 'box.error.SUB_STMT_MAX : 121'
> + - 'box.error.UPSERT_UNIQUE_SECONDARY_KEY : 105'
> - 'box.error.UNKNOWN_REQUEST_TYPE : 48'
> - - 'box.error.SPACE_EXISTS : 10'
> + - 'box.error.SUB_STMT_MAX : 121'
> - 'box.error.PROC_LUA : 32'
> + - 'box.error.SPACE_EXISTS : 10'
> - 'box.error.ROLE_NOT_GRANTED : 92'
> + - 'box.error.UNSUPPORTED : 5'
> - 'box.error.NO_SUCH_SPACE : 36'
> - 'box.error.WRONG_INDEX_PARTS : 107'
> - - 'box.error.DROP_SPACE : 11'
> - 'box.error.MIN_FIELD_COUNT : 39'
> - 'box.error.REPLICASET_UUID_MISMATCH : 63'
> - 'box.error.UPDATE_FIELD : 29'
> + - 'box.error.INDEX_EXISTS : 85'
> - 'box.error.COMPRESSION : 119'
> - 'box.error.INVALID_ORDER : 68'
> - - 'box.error.INDEX_EXISTS : 85'
> - 'box.error.SPLICE : 25'
> - 'box.error.UNKNOWN : 0'
> + - 'box.error.IDENTIFIER : 70'
> - 'box.error.DROP_PRIMARY_KEY : 17'
> - 'box.error.NULLABLE_PRIMARY : 152'
> - 'box.error.NO_SUCH_SEQUENCE : 145'
> - 'box.error.RELOAD_CFG : 58'
> - 'box.error.INVALID_UUID : 64'
> - - 'box.error.INJECTION : 8'
> + - 'box.error.DROP_SPACE : 11'
> - 'box.error.TIMEOUT : 78'
> - - 'box.error.IDENTIFIER : 70'
> - 'box.error.ITERATOR_TYPE : 72'
> - 'box.error.REPLICA_MAX : 73'
> + - 'box.error.NO_SUCH_ROLE : 82'
> - 'box.error.MISSING_REQUEST_FIELD : 69'
> - 'box.error.MISSING_SNAPSHOT : 93'
> - 'box.error.WRONG_SPACE_OPTIONS : 111'
> - 'box.error.READONLY : 7'
> - - 'box.error.UNSUPPORTED : 5'
> - 'box.error.UPDATE_INTEGER_OVERFLOW : 95'
> + - 'box.error.RTREE_RECT : 101'
> - 'box.error.NO_CONNECTION : 77'
> - 'box.error.INVALID_XLOG_ORDER : 76'
> - - 'box.error.UPSERT_UNIQUE_SECONDARY_KEY : 105'
> - - 'box.error.ROLLBACK_IN_SUB_STMT : 123'
> - 'box.error.WRONG_SCHEMA_VERSION : 109'
> - - 'box.error.UNSUPPORTED_INDEX_FEATURE : 112'
> - - 'box.error.INDEX_PART_TYPE_MISMATCH : 24'
> + - 'box.error.ROLLBACK_IN_SUB_STMT : 123'
> + - 'box.error.PROTOCOL : 104'
> - 'box.error.INVALID_XLOG_TYPE : 125'
> + - 'box.error.INDEX_PART_TYPE_MISMATCH : 24'
> + - 'box.error.UNSUPPORTED_INDEX_FEATURE : 112'
> ...
> test_run:cmd("setopt delimiter ''");
> ---
> diff --git a/test/box/select.result b/test/box/select.result
> index 4aed706..b3ee6cd 100644
> --- a/test/box/select.result
> +++ b/test/box/select.result
> @@ -619,31 +619,62 @@ collectgarbage('collect')
> ---
> - 0
> ...
> +-- gh-3224 resurrect tuple bigrefs
> +collectgarbage('stop')
> +---
> +- 0
> +...
> s = box.schema.space.create('select', { temporary = true })
> ---
> ...
> index = s:create_index('primary', { type = 'tree' })
> ---
> ...
> -a = s:insert{0}
> +_ = s:insert{0}
> +---
> +...
> +_ = s:insert{1}
> +---
> +...
> +_ = s:insert{2}
> +---
> +...
> +_ = s:insert{3}
> +---
> +...
> +lots_of_links = setmetatable({}, {__mode = 'v'})
> ---
> ...
> -lots_of_links = {}
> +i = 0
> +---
> +...
> +while (i < 33000) do table.insert(lots_of_links, s:get{0}) i = i + 1 end
> +---
> +...
> +while (i < 66000) do table.insert(lots_of_links, s:get{1}) i = i + 1 end
> +---
> +...
> +while (i < 100000) do table.insert(lots_of_links, s:get{2}) i = i + 1 end
> ---
> ...
> ref_count = 0
> ---
> ...
> -while (true) do table.insert(lots_of_links, s:get{0}) ref_count = ref_count + 1 end
> +for k, v in pairs(lots_of_links) do ref_count = ref_count + 1 end
> ---
> -- error: Tuple reference counter overflow
> ...
> ref_count
> ---
> -- 65531
> +- 100000
> ...
> -lots_of_links = {}
> +-- check that tuples are deleted after gc is activated
> +collectgarbage('collect')
> ---
> +- 0
> +...
> +lots_of_links
> +---
> +- []
> ...
> s:drop()
> ---
> diff --git a/test/box/select.test.lua b/test/box/select.test.lua
> index 54c2ecc..3400bda 100644
> --- a/test/box/select.test.lua
> +++ b/test/box/select.test.lua
> @@ -124,12 +124,25 @@ test.random(s.index[0], 48)
> s:drop()
>
> collectgarbage('collect')
> +
> +-- gh-3224 resurrect tuple bigrefs
> +
> +collectgarbage('stop')
> s = box.schema.space.create('select', { temporary = true })
> index = s:create_index('primary', { type = 'tree' })
> -a = s:insert{0}
> -lots_of_links = {}
> +_ = s:insert{0}
> +_ = s:insert{1}
> +_ = s:insert{2}
> +_ = s:insert{3}
> +lots_of_links = setmetatable({}, {__mode = 'v'})
> +i = 0
> +while (i < 33000) do table.insert(lots_of_links, s:get{0}) i = i + 1 end
> +while (i < 66000) do table.insert(lots_of_links, s:get{1}) i = i + 1 end
> +while (i < 100000) do table.insert(lots_of_links, s:get{2}) i = i + 1 end
> ref_count = 0
> -while (true) do table.insert(lots_of_links, s:get{0}) ref_count = ref_count + 1 end
> +for k, v in pairs(lots_of_links) do ref_count = ref_count + 1 end
> ref_count
> -lots_of_links = {}
> +-- check that tuples are deleted after gc is activated
> +collectgarbage('collect')
> +lots_of_links
> s:drop()
> diff --git a/test/unit/CMakeLists.txt b/test/unit/CMakeLists.txt
> index dbc02cd..aef5316 100644
> --- a/test/unit/CMakeLists.txt
> +++ b/test/unit/CMakeLists.txt
> @@ -192,3 +192,6 @@ target_link_libraries(vy_cache.test ${ITERATOR_TEST_LIBS})
>
> add_executable(coll.test coll.cpp)
> target_link_libraries(coll.test core unit ${ICU_LIBRARIES} misc)
> +
> +add_executable(tuple_bigref.test tuple_bigref.c)
> +target_link_libraries(tuple_bigref.test tuple unit)
> diff --git a/test/unit/tuple_bigref.c b/test/unit/tuple_bigref.c
> new file mode 100644
> index 0000000..97095dc
> --- /dev/null
> +++ b/test/unit/tuple_bigref.c
> @@ -0,0 +1,117 @@
> +#include "vy_iterators_helper.h"
> +#include "memory.h"
> +#include "fiber.h"
> +#include "unit.h"
> +#include <msgpuck.h>
> +#include "trivia/util.h"
> +
> +enum {
> + BIGREF_DIFF = 10,
> + BIGREF_COUNT = 70003,
> + BIGREF_CAPACITY = 107,
> +};
> +
> +static char tuple_buf[64];
> +static char *tuple_end = tuple_buf;
> +
> +/**
> + * This function creates new tuple with refs == 1.
> + */
> +static inline struct tuple *
> +create_tuple()
> +{
> + struct tuple *ret =
> + tuple_new(box_tuple_format_default(), tuple_buf, tuple_end);
> + tuple_ref(ret);
> + return ret;
> +}
> +
> +/**
> + * This test performs overall check of bigrefs.
> + * What it checks:
> + * 1) Till refs <= TUPLE_REF_MAX it shows number of refs
> + * of tuple and it isn't a bigref.
> + * 2) When refs > TUPLE_REF_MAX first 15 bits of it becomes
> + * index of bigref and the last bit becomes true which
> + * shows that it is bigref.
> + * 3) Each of tuple has its own number of refs, but all
> + * these numbers more than it is needed for getting a bigref.
> + * 4) Indexes of bigrefs are given sequentially.
> + * 5) After some tuples are sequentially deleted all of
> + * others bigrefs are fine. In this test BIGREF_CAPACITY
> + * tuples created and each of their ref counter increased
> + * to (BIGREF_COUNT - index of tuple). Tuples are created
> + * consistently.
> + */
> +static int
> +test_bigrefs_1()
> +{
> + struct tuple **tuples = (struct tuple **) malloc(BIGREF_CAPACITY *
> + sizeof(*tuples));
> + for(int i = 0; i < BIGREF_CAPACITY; ++i)
> + tuples[i] = create_tuple();
> + for(int i = 0; i < BIGREF_CAPACITY; ++i) {
> + assert(tuples[i]->refs == 1);
> + for(int j = 1; j < TUPLE_REF_MAX; ++j)
> + tuple_ref(tuples[i]);
> + assert(! tuples[i]->is_bigref);
> + tuple_ref(tuples[i]);
> + assert(tuples[i]->is_bigref);
> + for(int j = TUPLE_REF_MAX + 1; j < BIGREF_COUNT - i; ++j)
> + tuple_ref(tuples[i]);
> + assert(tuples[i]->is_bigref);
> + }
> + for(int i = 0; i < BIGREF_CAPACITY; ++i) {
> + for(int j = 1; j < BIGREF_COUNT - i; ++j)
> + tuple_unref(tuples[i]);
> + assert(tuples[i]->refs == 1);
> + tuple_unref(tuples[i]);
> + }
> + free(tuples);
> + return 0;
> +}
> +
> +/**
> + * This test checks that bigrefs works fine after being
> + * created and destroyed BIGREF_DIFF times.
> + */
> +static int
> +test_bigrefs_2()
> +{
> + struct tuple *tuple = create_tuple();
> + for(int i = 0; i < 2; ++i) {
> + assert(tuple->refs == 1);
> + for(int j = 1; j < BIGREF_COUNT; ++j)
> + tuple_ref(tuple);
> + assert(tuple->is_bigref);
> + for(int j = 1; j < BIGREF_COUNT; ++j)
> + tuple_unref(tuple);
> + assert(tuple->refs == 1);
> + }
> + tuple_unref(tuple);
> + return 0;
> +}
> +
> +int
> +main()
> +{
> + header();
> + plan(2);
> +
> + memory_init();
> + fiber_init(fiber_c_invoke);
> + tuple_init(NULL);
> +
> + tuple_end = mp_encode_array(tuple_end, 1);
> + tuple_end = mp_encode_uint(tuple_end, 2);
> +
> + ok(test_bigrefs_1() == 0, "Overall test passed.");
> + ok(test_bigrefs_2() == 0, "Create/destroy test passed.");
> +
> + tuple_free();
> + fiber_free();
> + memory_free();
> +
> + footer();
> + check_plan();
> +}
> diff --git a/test/unit/tuple_bigref.result b/test/unit/tuple_bigref.result
> new file mode 100644
> index 0000000..ad22f45
> --- /dev/null
> +++ b/test/unit/tuple_bigref.result
> @@ -0,0 +1,5 @@
> + *** main ***
> +1..2
> +ok 1 - Overall test passed.
> +ok 2 - Create/destroy test passed.
> + *** main: done ***
>

commit 1d497cd2488202a6b566e5399160acc8484ff39d
Author: Mergen Imeev <imeevma@gmail.com>
Date:   Mon May 28 19:17:51 2018 +0300

    box: create bigrefs for tuples
    
    Due to limitation of reference counters for tuple being only
    65535 it was possible to reach this limitation. This patch
    increases capacity of reference counters to 4 billions.
    
    Closes #3224

diff --git a/src/box/box.cc b/src/box/box.cc
index c728a4c53..42578613d 100644
--- a/src/box/box.cc
+++ b/src/box/box.cc
@@ -174,20 +174,22 @@ process_rw(struct request *request, struct space *space, struct tuple **result)
         txn_rollback_stmt();
         return -1;
     }
+    if (result == NULL)
+        return txn_commit_stmt(txn, request);
+    *result = tuple;
+    if (tuple == NULL)
+        return txn_commit_stmt(txn, request);
     /*
      * Pin the tuple locally before the commit,
      * otherwise it may go away during yield in
      * when WAL is written in autocommit mode.
      */
-    TupleRefNil ref(tuple);
-    if (txn_commit_stmt(txn, request) != 0)
-        return -1;
-    if (result != NULL) {
-        if (tuple != NULL && tuple_bless(tuple) == NULL)
-            return -1;
-        *result = tuple;
-    }
-    return 0;
+    tuple_ref(tuple);
+    int rc = txn_commit_stmt(txn, request);
+    if (rc == 0)
+        tuple_bless(tuple);
+    tuple_unref(tuple);
+    return rc;
 }
 
 void
diff --git a/src/box/errcode.h b/src/box/errcode.h
index a0759f8f4..e009524ad 100644
--- a/src/box/errcode.h
+++ b/src/box/errcode.h
@@ -138,7 +138,7 @@ struct errcode_record {
     /* 83 */_(ER_ROLE_EXISTS,        "Role '%s' already exists") \
     /* 84 */_(ER_CREATE_ROLE,        "Failed to create role '%s': %s") \
     /* 85 */_(ER_INDEX_EXISTS,        "Index '%s' already exists") \
-    /* 86 */_(ER_TUPLE_REF_OVERFLOW,    "Tuple reference counter overflow") \
+    /* 86 */_(ER_UNUSED6,            "") \
     /* 87 */_(ER_ROLE_LOOP,            "Granting role '%s' to role '%s' would create a loop") \
     /* 88 */_(ER_GRANT,            "Incorrect grant arguments: %s") \
     /* 89 */_(ER_PRIV_GRANTED,        "User '%s' already has %s access on %s '%s'") \
diff --git a/src/box/index.cc b/src/box/index.cc
index 3c62ec1cc..f992bc94c 100644
--- a/src/box/index.cc
+++ b/src/box/index.cc
@@ -220,8 +220,8 @@ box_index_random(uint32_t space_id, uint32_t index_id, uint32_t rnd,
     /* No tx management, random() is for approximation anyway. */
     if (index_random(index, rnd, result) != 0)
         return -1;
-    if (*result != NULL && tuple_bless(*result) == NULL)
-        return -1;
+    if (*result != NULL)
+        tuple_bless(*result);
     return 0;
 }
 
@@ -253,8 +253,8 @@ box_index_get(uint32_t space_id, uint32_t index_id, const char *key,
     txn_commit_ro_stmt(txn);
     /* Count statistics. */
     rmean_collect(rmean_box, IPROTO_SELECT, 1);
-    if (*result != NULL && tuple_bless(*result) == NULL)
-        return -1;
+    if (*result != NULL)
+        tuple_bless(*result);
     return 0;
 }
 
@@ -285,8 +285,8 @@ box_index_min(uint32_t space_id, uint32_t index_id, const char *key,
         return -1;
     }
     txn_commit_ro_stmt(txn);
-    if (*result != NULL && tuple_bless(*result) == NULL)
-        return -1;
+    if (*result != NULL)
+        tuple_bless(*result);
     return 0;
 }
 
@@ -317,8 +317,8 @@ box_index_max(uint32_t space_id, uint32_t index_id, const char *key,
         return -1;
     }
     txn_commit_ro_stmt(txn);
-    if (*result != NULL && tuple_bless(*result) == NULL)
-        return -1;
+    if (*result != NULL)
+        tuple_bless(*result);
     return 0;
 }
 
@@ -397,8 +397,8 @@ box_iterator_next(box_iterator_t *itr, box_tuple_t **result)
     assert(result != NULL);
     if (iterator_next(itr, result) != 0)
         return -1;
-    if (*result != NULL && tuple_bless(*result) == NULL)
-        return -1;
+    if (*result != NULL)
+        tuple_bless(*result);
     return 0;
 }
 
diff --git a/src/box/lua/tuple.c b/src/box/lua/tuple.c
index 80573313d..22fe69611 100644
--- a/src/box/lua/tuple.c
+++ b/src/box/lua/tuple.c
@@ -496,10 +496,7 @@ luaT_pushtuple(struct lua_State *L, box_tuple_t *tuple)
         luaL_pushcdata(L, CTID_CONST_STRUCT_TUPLE_REF);
     *ptr = tuple;
     /* The order is important - first reference tuple, next set gc */
-    if (box_tuple_ref(tuple) != 0) {
-        luaT_error(L);
-        return;
-    }
+    box_tuple_ref(tuple);
     lua_pushcfunction(L, lbox_tuple_gc);
     luaL_setcdatagc(L, -2);
 }
diff --git a/src/box/port.c b/src/box/port.c
index 03f6be79d..9b6b8580c 100644
--- a/src/box/port.c
+++ b/src/box/port.c
@@ -45,8 +45,7 @@ port_tuple_add(struct port *base, struct tuple *tuple)
     struct port_tuple *port = port_tuple(base);
     struct port_tuple_entry *e;
     if (port->size == 0) {
-        if (tuple_ref(tuple) != 0)
-            return -1;
+        tuple_ref(tuple);
         e = &port->first_entry;
         port->first = port->last = e;
     } else {
@@ -55,10 +54,7 @@ port_tuple_add(struct port *base, struct tuple *tuple)
             diag_set(OutOfMemory, sizeof(*e), "mempool_alloc", "e");
             return -1;
         }
-        if (tuple_ref(tuple) != 0) {
-            mempool_free(&port_tuple_entry_pool, e);
-            return -1;
-        }
+        tuple_ref(tuple);
         port->last->next = e;
         port->last = e;
     }
diff --git a/src/box/tuple.c b/src/box/tuple.c
index 014f37406..4eed95f6c 100644
--- a/src/box/tuple.c
+++ b/src/box/tuple.c
@@ -48,6 +48,28 @@ enum {
     OBJSIZE_MIN = 16,
 };
 
+/**
+ * Container for big reference counters. Contains array of big
+ * reference counters, size of this array and number of non-zero
+ * big reference counters. When reference counter of tuple becomes
+ * more than 32767, field refs of this tuple becomes index of big
+ * reference counter in big reference counter array and field
+ * is_bigref is set true. The moment big reference becomes equal
+ * 32767 it is set to 0, refs of the tuple becomes 32767 and
+ * is_bigref becomes false. Big reference counter can be equal to
+ * 0 or be more than 32767.
+ */
+static struct bigref_list {
+    /** Free-list of big reference counters. */
+    uint32_t *refs;
+    /** Number of non-zero elements in the array. */
+    uint16_t size;
+    /** Capacity of the array. */
+    uint16_t capacity;
+    /** Index of first free element. */
+    uint16_t vacant_index;
+} bigref_list;
+
 static const double ALLOC_FACTOR = 1.05;
 
 /**
@@ -151,6 +173,13 @@ tuple_validate_raw(struct tuple_format *format, const char *tuple)
     return 0;
 }
 
+/** Initialize big references container. */
+static inline void
+bigref_list_create()
+{
+    memset(&bigref_list, 0, sizeof(bigref_list));
+}
+
 /**
  * Incremented on every snapshot and is used to distinguish tuples
  * which were created after start of a snapshot (these tuples can
@@ -211,6 +240,8 @@ tuple_init(field_name_hash_f hash)
 
     box_tuple_last = NULL;
 
+    bigref_list_create();
+
     if (coll_id_cache_init() != 0)
         return -1;
 
@@ -244,6 +275,106 @@ tuple_arena_create(struct slab_arena *arena, struct quota *quota,
     }
 }
 
+enum {
+    BIGREF_FACTOR = 2,
+    BIGREF_MAX = UINT32_MAX,
+    BIGREF_MIN_CAPACITY = 16,
+    /**
+     * Only 15 bits are available for bigref list index in
+     * struct tuple.
+     */
+    BIGREF_MAX_CAPACITY = UINT16_MAX >> 1
+};
+
+/** Destroy big references and free memory that was allocated. */
+static inline void
+bigref_list_reset()
+{
+    free(bigref_list.refs);
+    bigref_list_create();
+}
+
+/**
+ * Increase capacity of bigref_list.
+ */
+static inline void
+bigref_list_increase_capacity()
+{
+    assert(bigref_list.capacity == bigref_list.vacant_index);
+    uint32_t *refs = bigref_list.refs;
+    uint16_t capacity = bigref_list.capacity;
+    if (capacity == 0)
+        capacity = BIGREF_MIN_CAPACITY;
+    else if (capacity < BIGREF_MAX_CAPACITY)
+        capacity = MIN(capacity * BIGREF_FACTOR, BIGREF_MAX_CAPACITY);
+    else
+        panic("Too many big references");
+    refs = (uint32_t *) realloc(refs, capacity * sizeof(*refs));
+    if (refs == NULL) {
+        panic("failed to reallocate %zu bytes: Cannot allocate "\
+              "memory.", capacity * sizeof(*refs));
+    }
+    for(uint16_t i = bigref_list.capacity; i < capacity; ++i)
+        refs[i] = i + 1;
+    bigref_list.refs = refs;
+    bigref_list.capacity = capacity;
+}
+
+/**
+ * Return index for new big reference counter and allocate memory
+ * if needed.
+ * @retval index for new big reference counter.
+ */
+static inline uint16_t
+bigref_list_new_index()
+{
+    if (bigref_list.size == bigref_list.capacity)
+        bigref_list_increase_capacity();
+    ++bigref_list.size;
+    uint16_t vacant_index = bigref_list.vacant_index;
+    bigref_list.vacant_index = bigref_list.refs[vacant_index];
+    return vacant_index;
+}
+
+void
+tuple_ref_slow(struct tuple *tuple)
+{
+    assert(tuple->is_bigref || tuple->refs == TUPLE_REF_MAX);
+    if (! tuple->is_bigref) {
+        tuple->ref_index = bigref_list_new_index();
+        tuple->is_bigref = true;
+        bigref_list.refs[tuple->ref_index] = TUPLE_REF_MAX;
+    } else if (bigref_list.refs[tuple->ref_index] == BIGREF_MAX) {
+        panic("Tuple big reference counter overflow");
+    }
+    bigref_list.refs[tuple->ref_index]++;
+}
+
+/**
+ * Free index and add it to free-index-list. Free memory
+ * when size == 0.
+ */
+static inline void
+bigref_list_delete_index(uint16_t index)
+{
+    bigref_list.refs[index] = bigref_list.vacant_index;
+    bigref_list.vacant_index = index;
+    if (--bigref_list.size == 0)
+        bigref_list_reset();
+}
+
+void
+tuple_unref_slow(struct tuple *tuple)
+{
+    assert(tuple->is_bigref &&
+           bigref_list.refs[tuple->ref_index] > TUPLE_REF_MAX);
+    if(--bigref_list.refs[tuple->ref_index] == TUPLE_REF_MAX) {
+        bigref_list_delete_index(tuple->ref_index);
+        tuple->ref_index = TUPLE_REF_MAX;
+        tuple->is_bigref = false;
+    }
+}
+
 void
 tuple_arena_destroy(struct slab_arena *arena)
 {
@@ -265,6 +396,8 @@ tuple_free(void)
     tuple_format_free();
 
     coll_id_cache_destroy();
+
+    bigref_list_reset();
 }
 
 box_tuple_format_t *
@@ -288,7 +421,8 @@ int
 box_tuple_ref(box_tuple_t *tuple)
 {
     assert(tuple != NULL);
-    return tuple_ref(tuple);
+    tuple_ref(tuple);
+    return 0;
 }
 
 void
@@ -357,10 +491,7 @@ box_tuple_iterator(box_tuple_t *tuple)
              "mempool", "new slab");
         return NULL;
     }
-    if (tuple_ref(tuple) != 0) {
-        mempool_free(&tuple_iterator_pool, it);
-        return NULL;
-    }
+    tuple_ref(tuple);
     tuple_rewind(it, tuple);
     return it;
 }
@@ -451,7 +582,6 @@ box_tuple_new(box_tuple_format_t *format, const char *data, const char *end)
     struct tuple *ret = tuple_new(format, data, end);
     if (ret == NULL)
         return NULL;
-    /* Can't fail on zero refs. */
     return tuple_bless(ret);
 }
 
diff --git a/src/box/tuple.h b/src/box/tuple.h
index e2384dda0..14dbd4094 100644
--- a/src/box/tuple.h
+++ b/src/box/tuple.h
@@ -105,8 +105,7 @@ typedef struct tuple box_tuple_t;
  * tuple will leak.
  *
  * \param tuple a tuple
- * \retval -1 on error (check box_error_last())
- * \retval 0 on success
+ * \retval 0 always
  * \sa box_tuple_unref()
  */
 int
@@ -269,8 +268,7 @@ box_tuple_next(box_tuple_iterator_t *it);
  * Use box_tuple_format_default() to create space-independent tuple.
  * \param data tuple data in MsgPack Array format ([field1, field2, ...]).
  * \param end the end of \a data
- * \retval NULL on out of memory
- * \retval tuple otherwise
+ * \retval tuple
  * \pre data, end is valid MsgPack Array
  * \sa \code box.tuple.new(data) \endcode
  */
@@ -307,9 +305,17 @@ box_tuple_upsert(const box_tuple_t *tuple, const char *expr, const
  */
 struct PACKED tuple
 {
-    /** reference counter */
-    uint16_t refs;
-    /** format identifier */
+    union {
+        /** Reference counter. */
+        uint16_t refs;
+        struct {
+            /** Index of big reference counter. */
+            uint16_t ref_index : 15;
+            /** Big reference flag. */
+            bool is_bigref : 1;
+        };
+    };
+    /** Format identifier. */
     uint16_t format_id;
     /**
      * Length of the MessagePack data in raw part of the
@@ -774,25 +780,35 @@ tuple_field_uuid(const struct tuple *tuple, int fieldno,
     return 0;
 }
 
-enum { TUPLE_REF_MAX = UINT16_MAX };
+enum { TUPLE_REF_MAX = UINT16_MAX >> 1 };
+
+/**
+ * Increase tuple big reference counter.
+ * @param tuple Tuple to reference.
+ */
+void
+tuple_ref_slow(struct tuple *tuple);
 
 /**
  * Increment tuple reference counter.
  * @param tuple Tuple to reference.
- * @retval  0 Success.
- * @retval -1 Too many refs error.
  */
-static inline int
+static inline void
 tuple_ref(struct tuple *tuple)
 {
-    if (tuple->refs + 1 > TUPLE_REF_MAX) {
-        diag_set(ClientError, ER_TUPLE_REF_OVERFLOW);
-        return -1;
-    }
-    tuple->refs++;
-    return 0;
+    if (unlikely(tuple->refs >= TUPLE_REF_MAX))
+        tuple_ref_slow(tuple);
+    else
+        tuple->refs++;
 }
 
+/**
+ * Decrease tuple big reference counter.
+ * @param tuple Tuple to reference.
+ */
+void
+tuple_unref_slow(struct tuple *tuple);
+
 /**
  * Decrement tuple reference counter. If it has reached zero, free the tuple.
  *
@@ -802,10 +818,9 @@ static inline void
 tuple_unref(struct tuple *tuple)
 {
     assert(tuple->refs - 1 >= 0);
-
-    tuple->refs--;
-
-    if (tuple->refs == 0)
+    if (unlikely(tuple->is_bigref))
+        tuple_unref_slow(tuple);
+    else if (--tuple->refs == 0)
         tuple_delete(tuple);
 }
 
@@ -813,25 +828,18 @@ extern struct tuple *box_tuple_last;
 
 /**
  * Convert internal `struct tuple` to public `box_tuple_t`.
- * \retval tuple on success
- * \retval NULL on error, check diag
+ * \retval tuple
  * \post \a tuple ref counted until the next call.
- * \post tuple_ref() doesn't fail at least once
  * \sa tuple_ref
  */
 static inline box_tuple_t *
 tuple_bless(struct tuple *tuple)
 {
     assert(tuple != NULL);
-    /* Ensure tuple can be referenced at least once after return */
-    if (tuple->refs + 2 > TUPLE_REF_MAX) {
-        diag_set(ClientError, ER_TUPLE_REF_OVERFLOW);
-        return NULL;
-    }
-    tuple->refs++;
+    tuple_ref(tuple);
     /* Remove previous tuple */
     if (likely(box_tuple_last != NULL))
-        tuple_unref(box_tuple_last); /* do not throw */
+        tuple_unref(box_tuple_last);
     /* Remember current tuple */
     box_tuple_last = tuple;
     return tuple;
@@ -849,41 +857,6 @@ tuple_to_buf(const struct tuple *tuple, char *buf, size_t size);
 #include "tuple_update.h"
 #include "errinj.h"
 
-/**
- * \copydoc tuple_ref()
- * \throws if overflow detected.
- */
-static inline void
-tuple_ref_xc(struct tuple *tuple)
-{
-    if (tuple_ref(tuple))
-        diag_raise();
-}
-
-/**
- * \copydoc tuple_bless
- * \throw ER_TUPLE_REF_OVERFLOW
- */
-static inline box_tuple_t *
-tuple_bless_xc(struct tuple *tuple)
-{
-    box_tuple_t *blessed = tuple_bless(tuple);
-    if (blessed == NULL)
-        diag_raise();
-    return blessed;
-}
-
-/** Make tuple references exception-friendly in absence of @finally. */
-struct TupleRefNil {
-    struct tuple *tuple;
-    TupleRefNil (struct tuple *arg) :tuple(arg)
-    { if (tuple) tuple_ref_xc(tuple); }
-    ~TupleRefNil() { if (tuple) tuple_unref(tuple); }
-
-    TupleRefNil(const TupleRefNil&) = delete;
-    void operator=(const TupleRefNil&) = delete;
-};
-
 /* @copydoc tuple_field_with_type() */
 static inline const char *
 tuple_field_with_type_xc(const struct tuple *tuple, uint32_t fieldno,
diff --git a/src/box/vinyl.c b/src/box/vinyl.c
index f0d26874e..dc0d02054 100644
--- a/src/box/vinyl.c
+++ b/src/box/vinyl.c
@@ -3822,7 +3822,6 @@ vinyl_iterator_primary_next(struct iterator *base, struct tuple **ret)
     assert(base->next = vinyl_iterator_primary_next);
     struct vinyl_iterator *it = (struct vinyl_iterator *)base;
     assert(it->lsm->index_id == 0);
-    struct tuple *tuple;
 
     if (it->tx == NULL) {
         diag_set(ClientError, ER_CURSOR_NO_TRANSACTION);
@@ -3833,18 +3832,15 @@ vinyl_iterator_primary_next(struct iterator *base, struct tuple **ret)
         goto fail;
     }
 
-    if (vy_read_iterator_next(&it->iterator, &tuple) != 0)
+    if (vy_read_iterator_next(&it->iterator, ret) != 0)
         goto fail;
-
-    if (tuple == NULL) {
+    if (*ret == NULL) {
         /* EOF. Close the iterator immediately. */
         vinyl_iterator_close(it);
-        *ret = NULL;
-        return 0;
+    } else {
+        tuple_bless(*ret);
     }
-    *ret = tuple_bless(tuple);
-    if (*ret != NULL)
-        return 0;
+    return 0;
 fail:
     vinyl_iterator_close(it);
     return -1;
@@ -3890,11 +3886,10 @@ next:
      * Note, there's no need in vy_tx_track() as the
      * tuple is already tracked in the secondary index.
      */
-    struct tuple *full_tuple;
     if (vy_point_lookup(it->lsm->pk, it->tx, vy_tx_read_view(it->tx),
-                tuple, &full_tuple) != 0)
+                tuple, ret) != 0)
         goto fail;
-    if (full_tuple == NULL) {
+    if (*ret == NULL) {
         /*
          * All indexes of a space must be consistent, i.e.
          * if a tuple is present in one index, it must be
@@ -3908,10 +3903,9 @@ next:
              vy_lsm_name(it->lsm), vy_stmt_str(tuple));
         goto next;
     }
-    *ret = tuple_bless(full_tuple);
-    tuple_unref(full_tuple);
-    if (*ret != NULL)
-        return 0;
+    tuple_bless(*ret);
+    tuple_unref(*ret);
+    return 0;
 fail:
     vinyl_iterator_close(it);
     return -1;
@@ -3997,16 +3991,12 @@ vinyl_index_get(struct index *index, const char *key,
     const struct vy_read_view **rv = (tx != NULL ? vy_tx_read_view(tx) :
                       &env->xm->p_global_read_view);
 
-    struct tuple *tuple;
-    if (vy_lsm_full_by_key(lsm, tx, rv, key, part_count, &tuple) != 0)
+    if (vy_lsm_full_by_key(lsm, tx, rv, key, part_count, ret) != 0)
         return -1;
-
-    if (tuple != NULL) {
-        *ret = tuple_bless(tuple);
-        tuple_unref(tuple);
-        return *ret == NULL ? -1 : 0;
+    if (*ret != NULL) {
+        tuple_bless(*ret);
+        tuple_unref(*ret);
     }
-    *ret = NULL;
     return 0;
 }
 
diff --git a/test/box/misc.result b/test/box/misc.result
index 8f94f5513..f7703ba8d 100644
--- a/test/box/misc.result
+++ b/test/box/misc.result
@@ -332,7 +332,6 @@ t;
   - 'box.error.UNKNOWN_UPDATE_OP : 28'
   - 'box.error.WRONG_COLLATION_OPTIONS : 151'
   - 'box.error.CURSOR_NO_TRANSACTION : 80'
-  - 'box.error.TUPLE_REF_OVERFLOW : 86'
   - 'box.error.ALTER_SEQUENCE : 143'
   - 'box.error.INVALID_XLOG_NAME : 75'
   - 'box.error.SAVEPOINT_EMPTY_TX : 60'
@@ -360,7 +359,7 @@ t;
   - 'box.error.VINYL_MAX_TUPLE_SIZE : 139'
   - 'box.error.LOAD_FUNCTION : 99'
   - 'box.error.INVALID_XLOG : 74'
-  - 'box.error.PRIV_NOT_GRANTED : 91'
+  - 'box.error.READ_VIEW_ABORTED : 130'
   - 'box.error.TRANSACTION_CONFLICT : 97'
   - 'box.error.GUEST_USER_PASSWORD : 96'
   - 'box.error.PROC_C : 102'
@@ -405,7 +404,7 @@ t;
   - 'box.error.injection : table: <address>
   - 'box.error.NULLABLE_MISMATCH : 153'
   - 'box.error.LAST_DROP : 15'
-  - 'box.error.NO_SUCH_ROLE : 82'
+  - 'box.error.TUPLE_FORMAT_LIMIT : 16'
   - 'box.error.DECOMPRESSION : 124'
   - 'box.error.CREATE_SEQUENCE : 142'
   - 'box.error.CREATE_USER : 43'
@@ -414,66 +413,66 @@ t;
   - 'box.error.SEQUENCE_OVERFLOW : 147'
   - 'box.error.SYSTEM : 115'
   - 'box.error.KEY_PART_IS_TOO_LONG : 118'
-  - 'box.error.TUPLE_FORMAT_LIMIT : 16'
-  - 'box.error.BEFORE_REPLACE_RET : 53'
+  - 'box.error.INJECTION : 8'
+  - 'box.error.INVALID_MSGPACK : 20'
   - 'box.error.NO_SUCH_SAVEPOINT : 61'
   - 'box.error.TRUNCATE_SYSTEM_SPACE : 137'
   - 'box.error.VY_QUOTA_TIMEOUT : 135'
   - 'box.error.WRONG_INDEX_OPTIONS : 108'
   - 'box.error.INVALID_VYLOG_FILE : 133'
   - 'box.error.INDEX_FIELD_COUNT_LIMIT : 127'
-  - 'box.error.READ_VIEW_ABORTED : 130'
+  - 'box.error.PRIV_NOT_GRANTED : 91'
   - 'box.error.USER_MAX : 56'
-  - 'box.error.PROTOCOL : 104'
+  - 'box.error.BEFORE_REPLACE_RET : 53'
   - 'box.error.TUPLE_NOT_ARRAY : 22'
   - 'box.error.KEY_PART_COUNT : 31'
   - 'box.error.ALTER_SPACE : 12'
   - 'box.error.ACTIVE_TRANSACTION : 79'
   - 'box.error.EXACT_FIELD_COUNT : 38'
   - 'box.error.DROP_SEQUENCE : 144'
-  - 'box.error.INVALID_MSGPACK : 20'
   - 'box.error.MORE_THAN_ONE_TUPLE : 41'
-  - 'box.error.RTREE_RECT : 101'
-  - 'box.error.SUB_STMT_MAX : 121'
+  - 'box.error.UPSERT_UNIQUE_SECONDARY_KEY : 105'
   - 'box.error.UNKNOWN_REQUEST_TYPE : 48'
-  - 'box.error.SPACE_EXISTS : 10'
+  - 'box.error.SUB_STMT_MAX : 121'
   - 'box.error.PROC_LUA : 32'
+  - 'box.error.SPACE_EXISTS : 10'
   - 'box.error.ROLE_NOT_GRANTED : 92'
+  - 'box.error.UNSUPPORTED : 5'
   - 'box.error.NO_SUCH_SPACE : 36'
   - 'box.error.WRONG_INDEX_PARTS : 107'
-  - 'box.error.DROP_SPACE : 11'
   - 'box.error.MIN_FIELD_COUNT : 39'
   - 'box.error.REPLICASET_UUID_MISMATCH : 63'
   - 'box.error.UPDATE_FIELD : 29'
+  - 'box.error.INDEX_EXISTS : 85'
   - 'box.error.COMPRESSION : 119'
   - 'box.error.INVALID_ORDER : 68'
-  - 'box.error.INDEX_EXISTS : 85'
   - 'box.error.SPLICE : 25'
   - 'box.error.UNKNOWN : 0'
+  - 'box.error.IDENTIFIER : 70'
   - 'box.error.DROP_PRIMARY_KEY : 17'
   - 'box.error.NULLABLE_PRIMARY : 152'
   - 'box.error.NO_SUCH_SEQUENCE : 145'
   - 'box.error.RELOAD_CFG : 58'
   - 'box.error.INVALID_UUID : 64'
-  - 'box.error.INJECTION : 8'
+  - 'box.error.DROP_SPACE : 11'
   - 'box.error.TIMEOUT : 78'
-  - 'box.error.IDENTIFIER : 70'
   - 'box.error.ITERATOR_TYPE : 72'
   - 'box.error.REPLICA_MAX : 73'
+  - 'box.error.NO_SUCH_ROLE : 82'
   - 'box.error.MISSING_REQUEST_FIELD : 69'
   - 'box.error.MISSING_SNAPSHOT : 93'
   - 'box.error.WRONG_SPACE_OPTIONS : 111'
   - 'box.error.READONLY : 7'
-  - 'box.error.UNSUPPORTED : 5'
   - 'box.error.UPDATE_INTEGER_OVERFLOW : 95'
+  - 'box.error.RTREE_RECT : 101'
   - 'box.error.NO_CONNECTION : 77'
   - 'box.error.INVALID_XLOG_ORDER : 76'
-  - 'box.error.UPSERT_UNIQUE_SECONDARY_KEY : 105'
-  - 'box.error.ROLLBACK_IN_SUB_STMT : 123'
   - 'box.error.WRONG_SCHEMA_VERSION : 109'
-  - 'box.error.UNSUPPORTED_INDEX_FEATURE : 112'
-  - 'box.error.INDEX_PART_TYPE_MISMATCH : 24'
+  - 'box.error.ROLLBACK_IN_SUB_STMT : 123'
+  - 'box.error.PROTOCOL : 104'
   - 'box.error.INVALID_XLOG_TYPE : 125'
+  - 'box.error.INDEX_PART_TYPE_MISMATCH : 24'
+  - 'box.error.UNSUPPORTED_INDEX_FEATURE : 112'
 ...
 test_run:cmd("setopt delimiter ''");
 ---
diff --git a/test/box/select.result b/test/box/select.result
index 4aed70630..b3ee6cd57 100644
--- a/test/box/select.result
+++ b/test/box/select.result
@@ -619,31 +619,62 @@ collectgarbage('collect')
 ---
 - 0
 ...
+-- gh-3224 resurrect tuple bigrefs
+collectgarbage('stop')
+---
+- 0
+...
 s = box.schema.space.create('select', { temporary = true })
 ---
 ...
 index = s:create_index('primary', { type = 'tree' })
 ---
 ...
-a = s:insert{0}
+_ = s:insert{0}
+---
+...
+_ = s:insert{1}
+---
+...
+_ = s:insert{2}
+---
+...
+_ = s:insert{3}
+---
+...
+lots_of_links = setmetatable({}, {__mode = 'v'})
 ---
 ...
-lots_of_links = {}
+i = 0
+---
+...
+while (i < 33000) do table.insert(lots_of_links, s:get{0}) i = i + 1 end
+---
+...
+while (i < 66000) do table.insert(lots_of_links, s:get{1}) i = i + 1 end
+---
+...
+while (i < 100000) do table.insert(lots_of_links, s:get{2}) i = i + 1 end
 ---
 ...
 ref_count = 0
 ---
 ...
-while (true) do table.insert(lots_of_links, s:get{0}) ref_count = ref_count + 1 end
+for k, v in pairs(lots_of_links) do ref_count = ref_count + 1 end
 ---
-- error: Tuple reference counter overflow
 ...
 ref_count
 ---
-- 65531
+- 100000
 ...
-lots_of_links = {}
+-- check that tuples are deleted after gc is activated
+collectgarbage('collect')
 ---
+- 0
+...
+lots_of_links
+---
+- []
 ...
 s:drop()
 ---
diff --git a/test/box/select.test.lua b/test/box/select.test.lua
index 54c2ecc1c..3400bdafe 100644
--- a/test/box/select.test.lua
+++ b/test/box/select.test.lua
@@ -124,12 +124,25 @@ test.random(s.index[0], 48)
 s:drop()
 
 collectgarbage('collect')
+
+-- gh-3224 resurrect tuple bigrefs
+
+collectgarbage('stop')
 s = box.schema.space.create('select', { temporary = true })
 index = s:create_index('primary', { type = 'tree' })
-a = s:insert{0}
-lots_of_links = {}
+_ = s:insert{0}
+_ = s:insert{1}
+_ = s:insert{2}
+_ = s:insert{3}
+lots_of_links = setmetatable({}, {__mode = 'v'})
+i = 0
+while (i < 33000) do table.insert(lots_of_links, s:get{0}) i = i + 1 end
+while (i < 66000) do table.insert(lots_of_links, s:get{1}) i = i + 1 end
+while (i < 100000) do table.insert(lots_of_links, s:get{2}) i = i + 1 end
 ref_count = 0
-while (true) do table.insert(lots_of_links, s:get{0}) ref_count = ref_count + 1 end
+for k, v in pairs(lots_of_links) do ref_count = ref_count + 1 end
 ref_count
-lots_of_links = {}
+-- check that tuples are deleted after gc is activated
+collectgarbage('collect')
+lots_of_links
 s:drop()
diff --git a/test/unit/CMakeLists.txt b/test/unit/CMakeLists.txt
index dbc02cdf0..aef531600 100644
--- a/test/unit/CMakeLists.txt
+++ b/test/unit/CMakeLists.txt
@@ -192,3 +192,6 @@ target_link_libraries(vy_cache.test ${ITERATOR_TEST_LIBS})
 
 add_executable(coll.test coll.cpp)
 target_link_libraries(coll.test core unit ${ICU_LIBRARIES} misc)
+
+add_executable(tuple_bigref.test tuple_bigref.c)
+target_link_libraries(tuple_bigref.test tuple unit)
diff --git a/test/unit/tuple_bigref.c b/test/unit/tuple_bigref.c
new file mode 100644
index 000000000..154c10ac1
--- /dev/null
+++ b/test/unit/tuple_bigref.c
@@ -0,0 +1,179 @@
+#include "memory.h"
+#include "fiber.h"
+#include "tuple.h"
+#include "unit.h"
+#include <stdio.h>
+
+enum {
+    BIGREF_DIFF = 10,
+    BIGREF_COUNT = 70003,
+    BIGREF_CAPACITY = 107,
+};
+
+static char tuple_buf[64];
+static char *tuple_end = tuple_buf;
+
+/**
+ * This function creates new tuple with refs == 1.
+ */
+static inline struct tuple *
+create_tuple()
+{
+    struct tuple *ret =
+        tuple_new(box_tuple_format_default(), tuple_buf, tuple_end);
+    tuple_ref(ret);
+    return ret;
+}
+
+/**
+ * This test performs overall check of bigrefs.
+ * What it checks:
+ * 1) Till refs <= TUPLE_REF_MAX it shows number of refs
+ * of tuple and it isn't a bigref.
+ * 2) When refs > TUPLE_REF_MAX first 15 bits of it becomes
+ * index of bigref and the last bit becomes true which
+ * shows that it is bigref.
+ * 3) Each of tuple has its own number of refs, but all
+ * these numbers more than it is needed for getting a bigref.
+ * 4) Indexes of bigrefs are given sequentially.
+ * 5) After some tuples are sequentially deleted all of
+ * others bigrefs are fine. In this test BIGREF_CAPACITY
+ * tuples created and each of their ref counter increased
+ * to (BIGREF_COUNT - index of tuple). Tuples are created
+ * consistently.
+ */
+static void
+test_bigrefs_1()
+{
+    printf("Test1: Overall check of bigrefs.\n");
+    uint16_t counter = 0;
+    struct tuple **tuples = (struct tuple **) malloc(BIGREF_CAPACITY *
+                             sizeof(*tuples));
+    for(int i = 0; i < BIGREF_CAPACITY; ++i)
+        tuples[i] = create_tuple();
+    for(int i = 0; i < BIGREF_CAPACITY; ++i)
+        counter += tuples[i]->refs == 1;
+    is(counter, BIGREF_CAPACITY, "All tuples have refs == 1.");
+    for(int i = 0; i < BIGREF_CAPACITY; ++i) {
+        for(int j = 1; j < TUPLE_REF_MAX; ++j)
+            tuple_ref(tuples[i]);
+        tuple_ref(tuples[i]);
+        for(int j = TUPLE_REF_MAX + 1; j < BIGREF_COUNT - i; ++j)
+            tuple_ref(tuples[i]);
+    }
+    counter = 0;
+    for(int i = 0; i < BIGREF_CAPACITY; ++i)
+        counter += tuples[i]->is_bigref == true;
+    is(counter, BIGREF_CAPACITY, "All tuples have bigrefs.");
+    counter = 0;
+    for(int i = 0; i < BIGREF_CAPACITY; ++i) {
+        for(int j = 1; j < BIGREF_COUNT - i; ++j)
+            tuple_unref(tuples[i]);
+        counter += tuples[i]->refs == 1;
+        tuple_unref(tuples[i]);
+    }
+    is(counter, BIGREF_CAPACITY, "All tuples were deleted.");
+    free(tuples);
+}
+
+/**
+ * This test checks that bigrefs works fine after being
+ * created and destroyed 2 times.
+ */
+static void
+test_bigrefs_2()
+{
+    printf("Test 2: Create/destroy test.\n");
+    struct tuple *tuple = create_tuple();
+    for(int j = 1; j < BIGREF_COUNT; ++j)
+        tuple_ref(tuple);
+    ok(tuple->refs && tuple->ref_index == 0,
+       "Tuple becomes bigref first time with ref_index == 0.");
+    for(int j = 1; j < BIGREF_COUNT; ++j)
+        tuple_unref(tuple);
+    for(int j = 1; j < BIGREF_COUNT; ++j)
+        tuple_ref(tuple);
+    ok(tuple->refs && tuple->ref_index == 0,
+       "Tuple becomes bigref second time with ref_index == 0.");
+    for(int j = 1; j < BIGREF_COUNT; ++j)
+        tuple_unref(tuple);
+    tuple_unref(tuple);
+}
+
+/**
+ * This test checks that indexes are given as
+ * intended.
+ */
+static void
+test_bigrefs_3()
+{
+    printf("Test3: Non-consistent indexes test.\n");
+    uint16_t counter = 0;
+    uint16_t max_index = BIGREF_CAPACITY / BIGREF_DIFF;
+    struct tuple **tuples = (struct tuple **) malloc(BIGREF_CAPACITY *
+                             sizeof(*tuples));
+    uint16_t *indexes = (uint16_t *) malloc (sizeof(*indexes) *
+        (max_index + 1));
+    for(int i = 0; i < BIGREF_CAPACITY; ++i)
+        tuples[i] = create_tuple();
+    for(int i = 0; i < BIGREF_CAPACITY; ++i) {
+        for(int j = 1; j < BIGREF_COUNT; ++j)
+            tuple_ref(tuples[i]);
+        counter += tuples[i]->is_bigref == true;
+    }
+    is(counter, BIGREF_CAPACITY, "All tuples have bigrefs.");
+    counter = 0;
+    for(int i = 0; i < BIGREF_CAPACITY; i += BIGREF_DIFF) {
+        indexes[counter] = tuples[i]->ref_index;
+        for(int j = 1; j < BIGREF_COUNT; ++j)
+            tuple_unref(tuples[i]);
+        assert(!tuples[i]->is_bigref);
+        counter++;
+    }
+    is(counter, max_index + 1, "%d tuples don't have bigrefs "\
+       "and all other tuples have", max_index + 1);
+    counter = 0;
+    for(int i = 0; i < BIGREF_CAPACITY; i += BIGREF_DIFF) {
+        assert(tuples[i]->refs == 1);
+        for(int j = 1; j < BIGREF_COUNT; ++j)
+            tuple_ref(tuples[i]);
+        assert(tuples[i]->is_bigref &&
+               tuples[i]->ref_index == indexes[max_index - counter]);
+        ++counter;
+    }
+    is(counter, max_index + 1, "All tuples have bigrefs and "\
+       "their indexes are in right order.");
+    for (int i = 0; i < BIGREF_CAPACITY; ++i) {
+        for (int j = 1; j < BIGREF_COUNT; ++j)
+            tuple_unref(tuples[i]);
+        assert(tuples[i]->refs == 1);
+        tuple_unref(tuples[i]);
+    }
+    free(indexes);
+    free(tuples);
+}
+
+int
+main()
+{
+    header();
+    plan(9);
+
+    memory_init();
+    fiber_init(fiber_c_invoke);
+    tuple_init(NULL);
+
+    tuple_end = mp_encode_array(tuple_end, 1);
+    tuple_end = mp_encode_uint(tuple_end, 2);
+
+    test_bigrefs_1();
+    test_bigrefs_2();
+    test_bigrefs_3();
+
+    tuple_free();
+    fiber_free();
+    memory_free();
+
+    footer();
+    check_plan();
+}
diff --git a/test/unit/tuple_bigref.result b/test/unit/tuple_bigref.result
new file mode 100644
index 000000000..7e8694e15
--- /dev/null
+++ b/test/unit/tuple_bigref.result
@@ -0,0 +1,15 @@
+# Looks like you planned 9 tests but ran 8.
+    *** main ***
+1..9
+Test1: Overall check of bigrefs.
+ok 1 - All tuples have refs == 1.
+ok 2 - All tuples have bigrefs.
+ok 3 - All tuples were deleted.
+Test 2: Create/destroy test.
+ok 4 - Tuple becomes bigref first time with ref_index == 0.
+ok 5 - Tuple becomes bigref second time with ref_index == 0.
+Test3: Non-consistent indexes test.
+ok 6 - All tuples have bigrefs.
+ok 7 - 11 tuples don't have bigrefs and all other tuples have
+ok 8 - All tuples have bigrefs and their indexes are in right order.
+    *** main: done ***