* [tarantool-patches] [PATCH 1/2] [replication] [recovery] recover missing data
2018-03-29 16:15 [tarantool-patches] [PATCH 0/2] [replication] [recovery] recover missing data Konstantin Belyavskiy
@ 2018-03-29 16:15 ` Konstantin Belyavskiy
2018-03-30 11:17 ` Vladimir Davydov
2018-03-29 16:15 ` [tarantool-patches] [PATCH 2/2] " Konstantin Belyavskiy
1 sibling, 1 reply; 5+ messages in thread
From: Konstantin Belyavskiy @ 2018-03-29 16:15 UTC (permalink / raw)
To: tarantool-patches
Part 1 of 2.
Add vclock comparison as a new synchronization condition.
And update catch test as now it works as expected.
Closes #3210
---
branch: gh-3210-recover-missing-local-data-master-master
src/box/applier.cc | 16 +++++++++++-----
test/replication/catch.result | 5 +++--
2 files changed, 14 insertions(+), 7 deletions(-)
diff --git a/src/box/applier.cc b/src/box/applier.cc
index 6bfe5a99a..12bf1f0d2 100644
--- a/src/box/applier.cc
+++ b/src/box/applier.cc
@@ -305,7 +305,7 @@ applier_join(struct applier *applier)
* server is 1.6. Since we have
* not initialized replication
* vclock yet, do it now. In 1.7+
- * this vlcock is not used.
+ * this vclock is not used.
*/
xrow_decode_vclock_xc(&row, &replicaset.vclock);
}
@@ -370,6 +370,7 @@ applier_subscribe(struct applier *applier)
struct ev_io *coio = &applier->io;
struct ibuf *ibuf = &applier->ibuf;
struct xrow_header row;
+ struct vclock remote_vclock_at_subscribe;
xrow_encode_subscribe_xc(&row, &REPLICASET_UUID, &INSTANCE_UUID,
&replicaset.vclock);
@@ -411,9 +412,8 @@ applier_subscribe(struct applier *applier)
* In case of successful subscribe, the server
* responds with its current vclock.
*/
- struct vclock vclock;
- vclock_create(&vclock);
- xrow_decode_vclock_xc(&row, &vclock);
+ vclock_create(&remote_vclock_at_subscribe);
+ xrow_decode_vclock_xc(&row, &remote_vclock_at_subscribe);
}
/**
* Tarantool < 1.6.7:
@@ -452,8 +452,14 @@ applier_subscribe(struct applier *applier)
applier_set_state(applier, APPLIER_FOLLOW);
}
+ /*
+ * Must stay in read-only mode, until it synchronized.
+ * Check lag and compare local vclock with remote one.
+ */
if (applier->state == APPLIER_SYNC &&
- applier->lag <= replication_sync_lag) {
+ applier->lag <= replication_sync_lag &&
+ vclock_compare(&remote_vclock_at_subscribe,
+ &replicaset.vclock) <= 0) {
/* Applier is synced, switch to "follow". */
applier_set_state(applier, APPLIER_FOLLOW);
}
diff --git a/test/replication/catch.result b/test/replication/catch.result
index 7d61ad26f..05c1c243e 100644
--- a/test/replication/catch.result
+++ b/test/replication/catch.result
@@ -99,10 +99,11 @@ box.space.test ~= nil
...
d = box.space.test:delete{1}
---
+- error: Can't modify data because this instance is in read-only mode.
...
box.space.test:get(1) == nil
---
-- true
+- false
...
-- case #2: delete tuple by net.box
test_run:cmd("switch default")
@@ -118,7 +119,7 @@ c = net_box.connect(r_uri)
...
c.space.test:get(1) == nil
---
-- true
+- false
...
-- check sync
errinj.set("ERRINJ_RELAY_TIMEOUT", 0)
--
2.14.3 (Apple Git-98)
^ permalink raw reply [flat|nested] 5+ messages in thread
* [tarantool-patches] [PATCH 2/2] [replication] [recovery] recover missing data
2018-03-29 16:15 [tarantool-patches] [PATCH 0/2] [replication] [recovery] recover missing data Konstantin Belyavskiy
2018-03-29 16:15 ` [tarantool-patches] [PATCH 1/2] " Konstantin Belyavskiy
@ 2018-03-29 16:15 ` Konstantin Belyavskiy
2018-03-30 11:33 ` Vladimir Davydov
1 sibling, 1 reply; 5+ messages in thread
From: Konstantin Belyavskiy @ 2018-03-29 16:15 UTC (permalink / raw)
To: tarantool-patches
Part 2 of 2.
Recover missing local data from replica.
In case of sudden power-loss, if data was not written to WAL but
already sent to remote replica, local can't recover properly and
we have different datasets.
Fix it by using remote replica's data and LSN comparison.
Based on @GeorgyKirichenko proposal and @locker race free check.
Closes #3210
---
branch: gh-3210-recover-missing-local-data-master-master
src/box/relay.cc | 16 ++++-
src/box/wal.cc | 15 +++-
test/replication/recover_missing.result | 116 ++++++++++++++++++++++++++++++
test/replication/recover_missing.test.lua | 41 +++++++++++
test/replication/suite.ini | 2 +-
5 files changed, 185 insertions(+), 5 deletions(-)
create mode 100644 test/replication/recover_missing.result
create mode 100644 test/replication/recover_missing.test.lua
diff --git a/src/box/relay.cc b/src/box/relay.cc
index 2bd05ad5f..88de2a32b 100644
--- a/src/box/relay.cc
+++ b/src/box/relay.cc
@@ -110,6 +110,11 @@ struct relay {
struct vclock recv_vclock;
/** Replicatoin slave version. */
uint32_t version_id;
+ /**
+ * Local vclock at the moment of subscribe, used to check
+ * dataset on the other side and send missing data rows if any.
+ */
+ struct vclock local_vclock_at_subscribe;
/** Relay endpoint */
struct cbus_endpoint endpoint;
@@ -541,6 +546,7 @@ relay_subscribe(int fd, uint64_t sync, struct replica *replica,
relay.version_id = replica_version_id;
relay.replica = replica;
replica_set_relay(replica, &relay);
+ vclock_copy(&relay.local_vclock_at_subscribe, &replicaset.vclock);
int rc = cord_costart(&relay.cord, tt_sprintf("relay_%p", &relay),
relay_subscribe_f, &relay);
@@ -583,10 +589,16 @@ relay_send_row(struct xstream *stream, struct xrow_header *packet)
/*
* We're feeding a WAL, thus responding to SUBSCRIBE request.
* In that case, only send a row if it is not from the same replica
- * (i.e. don't send replica's own rows back).
+ * (i.e. don't send replica's own rows back) or if this row is
+ * missing on the other side (i.e. in case of sudden power-loss,
+ * data was not written to WAL, so remote master can't recover
+ * it). In this case packet's LSN is lower or equal then local
+ * master's LSN at the moment it has issued 'SUBSCRIBE' request.
*/
if (relay->replica == NULL ||
- packet->replica_id != relay->replica->id) {
+ packet->replica_id != relay->replica->id ||
+ packet->lsn <= vclock_get(&relay->local_vclock_at_subscribe,
+ packet->replica_id)) {
relay_send(relay, packet);
}
}
diff --git a/src/box/wal.cc b/src/box/wal.cc
index 4576cfe09..7ea8fe20b 100644
--- a/src/box/wal.cc
+++ b/src/box/wal.cc
@@ -770,8 +770,19 @@ wal_write(struct journal *journal, struct journal_entry *entry)
* and promote vclock.
*/
if ((*last)->replica_id == instance_id) {
- vclock_follow(&replicaset.vclock, instance_id,
- (*last)->lsn);
+ /*
+ * In master-master configuration, during sudden
+ * power-loss, if the data has not been written
+ * to WAL but have been already sent to others
+ * they will send the data back. In this case
+ * vclock has already been promoted in applier.
+ */
+ if (vclock_get(&replicaset.vclock,
+ instance_id) < (*last)->lsn) {
+ vclock_follow(&replicaset.vclock,
+ instance_id,
+ (*last)->lsn);
+ }
break;
}
--last;
diff --git a/test/replication/recover_missing.result b/test/replication/recover_missing.result
new file mode 100644
index 000000000..4c9c9b195
--- /dev/null
+++ b/test/replication/recover_missing.result
@@ -0,0 +1,116 @@
+env = require('test_run')
+---
+...
+test_run = env.new()
+---
+...
+SERVERS = { 'autobootstrap1', 'autobootstrap2', 'autobootstrap3' }
+---
+...
+-- Start servers
+test_run:create_cluster(SERVERS)
+---
+...
+-- Wait for full mesh
+test_run:wait_fullmesh(SERVERS)
+---
+...
+test_run:cmd("switch autobootstrap1")
+---
+- true
+...
+for i = 0, 9 do box.space.test:insert{i, 'test' .. i} end
+---
+...
+box.space.test:count()
+---
+- 10
+...
+test_run:cmd('switch default')
+---
+- true
+...
+vclock1 = test_run:get_vclock('autobootstrap1')
+---
+...
+vclock2 = test_run:wait_cluster_vclock(SERVERS, vclock1)
+---
+...
+test_run:cmd("switch autobootstrap2")
+---
+- true
+...
+box.space.test:count()
+---
+- 10
+...
+box.error.injection.set("ERRINJ_RELAY_TIMEOUT", 0.01)
+---
+- ok
+...
+test_run:cmd("stop server autobootstrap1")
+---
+- true
+...
+fio = require('fio')
+---
+...
+-- This test checks ability to recover missing local data
+-- from remote replica. See #3210.
+-- Delete data on first master and test that after restart,
+-- due to difference in vclock it will be able to recover
+-- all missing data from replica.
+-- Also check that there is no concurrency, i.e. master is
+-- in 'read-only' mode unless it receives all data.
+fio.unlink(fio.pathjoin(fio.abspath("."), string.format('autobootstrap1/%020d.xlog', 8)))
+---
+- true
+...
+test_run:cmd("start server autobootstrap1")
+---
+- true
+...
+test_run:cmd("switch autobootstrap1")
+---
+- true
+...
+for i = 10, 19 do box.space.test:insert{i, 'test' .. i} end
+---
+...
+fiber = require('fiber')
+---
+...
+fiber.sleep(0.1)
+---
+...
+box.space.test:select()
+---
+- - [0, 'test0']
+ - [1, 'test1']
+ - [2, 'test2']
+ - [3, 'test3']
+ - [4, 'test4']
+ - [5, 'test5']
+ - [6, 'test6']
+ - [7, 'test7']
+ - [8, 'test8']
+ - [9, 'test9']
+ - [10, 'test10']
+ - [11, 'test11']
+ - [12, 'test12']
+ - [13, 'test13']
+ - [14, 'test14']
+ - [15, 'test15']
+ - [16, 'test16']
+ - [17, 'test17']
+ - [18, 'test18']
+ - [19, 'test19']
+...
+-- Cleanup.
+test_run:cmd('switch default')
+---
+- true
+...
+test_run:drop_cluster(SERVERS)
+---
+...
diff --git a/test/replication/recover_missing.test.lua b/test/replication/recover_missing.test.lua
new file mode 100644
index 000000000..775d23a0b
--- /dev/null
+++ b/test/replication/recover_missing.test.lua
@@ -0,0 +1,41 @@
+env = require('test_run')
+test_run = env.new()
+
+SERVERS = { 'autobootstrap1', 'autobootstrap2', 'autobootstrap3' }
+-- Start servers
+test_run:create_cluster(SERVERS)
+-- Wait for full mesh
+test_run:wait_fullmesh(SERVERS)
+
+test_run:cmd("switch autobootstrap1")
+for i = 0, 9 do box.space.test:insert{i, 'test' .. i} end
+box.space.test:count()
+
+test_run:cmd('switch default')
+vclock1 = test_run:get_vclock('autobootstrap1')
+vclock2 = test_run:wait_cluster_vclock(SERVERS, vclock1)
+
+test_run:cmd("switch autobootstrap2")
+box.space.test:count()
+box.error.injection.set("ERRINJ_RELAY_TIMEOUT", 0.01)
+test_run:cmd("stop server autobootstrap1")
+fio = require('fio')
+-- This test checks ability to recover missing local data
+-- from remote replica. See #3210.
+-- Delete data on first master and test that after restart,
+-- due to difference in vclock it will be able to recover
+-- all missing data from replica.
+-- Also check that there is no concurrency, i.e. master is
+-- in 'read-only' mode unless it receives all data.
+fio.unlink(fio.pathjoin(fio.abspath("."), string.format('autobootstrap1/%020d.xlog', 8)))
+test_run:cmd("start server autobootstrap1")
+
+test_run:cmd("switch autobootstrap1")
+for i = 10, 19 do box.space.test:insert{i, 'test' .. i} end
+fiber = require('fiber')
+fiber.sleep(0.1)
+box.space.test:select()
+
+-- Cleanup.
+test_run:cmd('switch default')
+test_run:drop_cluster(SERVERS)
diff --git a/test/replication/suite.ini b/test/replication/suite.ini
index ee76a3b00..b538f9625 100644
--- a/test/replication/suite.ini
+++ b/test/replication/suite.ini
@@ -3,7 +3,7 @@ core = tarantool
script = master.lua
description = tarantool/box, replication
disabled = consistent.test.lua
-release_disabled = catch.test.lua errinj.test.lua gc.test.lua before_replace.test.lua quorum.test.lua
+release_disabled = catch.test.lua errinj.test.lua gc.test.lua before_replace.test.lua quorum.test.lua recover_missing.test.lua
config = suite.cfg
lua_libs = lua/fast_replica.lua
long_run = prune.test.lua
--
2.14.3 (Apple Git-98)
^ permalink raw reply [flat|nested] 5+ messages in thread