Re: [RFC PATCH 01/23] vinyl: do not turn REPLACE into INSERT when processing DML request

[Vladimir Davydov <vdavydov.dev@gmail.com>]

On Wed, Jul 11, 2018 at 10:57:36AM +0300, Vladimir Davydov wrote:
> On Tue, Jul 10, 2018 at 09:39:09PM +0300, Konstantin Osipov wrote:
> > * Vladimir Davydov <vdavydov.dev@gmail.com> [18/07/10 15:22]:
> > > On Tue, Jul 10, 2018 at 03:15:27PM +0300, Konstantin Osipov wrote:
> > > > * Vladimir Davydov <vdavydov.dev@gmail.com> [18/07/08 22:52]:
> > > > > Since in presence of secondary indexes we read the primary index when
> > > > > processing a REPLACE request anyway, we turn it into INSERT if no tuple
> > > > > matching the new tuple is found so that INSERT+DELETE gets annihilated
> > > > > on compaction.
> > > > > 
> > > > > However, in the scope of #2129 we are planning to optimize the read out
> > > > > so that this transformation won't be possible anymore. So let's remove
> > > > > it now.
> > > > 
> > > > Ugh. What if we deal with a space which has a unique secondary
> > > > key, so optimization B is not applicable. You removed optimization
> > > > A for all spaces. 
> > > 
> > > The optimization works even if secondary indexes are unique.
> > 
> > Only for deletes. But not for replace/upsert.
> 
> It works for REPLACE as well.
> 
> > 
> > I thought you had the opinion that this optimization is
> > controversial - so ideally it should be optional. What do you
> > think now? Or you generally think that it's so controversial it's
> > not worth it, and if we do, we should not make it optional?
> 
> I made it mandatory for the sake of testing. We might want to make it
> optional one day - it isn't going to be a problem.

I removed this patch from the series and updated the branch. The only
patch that required manual rebase was

  [RFC PATCH 05/23] vinyl: fold vy_replace_one and vy_replace_impl

Posting the new version here:

From e0782b9d1b1d2bfc68aa2d460603281caaaaca17 Mon Sep 17 00:00:00 2001
From: Vladimir Davydov <vdavydov.dev@gmail.com>
Date: Sat, 23 Jun 2018 21:47:25 +0300
Subject: [PATCH] vinyl: fold vy_replace_one and vy_replace_impl

There's no point in separating REPLACE path between the cases when
the space has secondary indexes and when it only has the primary
index, because they are quite similar. Let's fold vy_replace_one
and vy_replace_impl into vy_replace to remove code duplication.

diff --git a/src/box/vinyl.c b/src/box/vinyl.c
index c95d05c1..44f8afaa 100644
--- a/src/box/vinyl.c
+++ b/src/box/vinyl.c
@@ -1540,160 +1540,6 @@ vy_insert_secondary(struct vy_env *env, struct vy_tx *tx, struct space *space,
 }
 
 /**
- * Execute REPLACE in a space with a single index, possibly with
- * lookup for an old tuple if the space has at least one
- * on_replace trigger.
- * @param env     Vinyl environment.
- * @param tx      Current transaction.
- * @param space   Space in which replace.
- * @param request Request with the tuple data.
- * @param stmt    Statement for triggers is filled with old
- *                statement.
- *
- * @retval  0 Success.
- * @retval -1 Memory error OR duplicate key error OR the primary
- *            index is not found OR a tuple reference increment
- *            error.
- */
-static inline int
-vy_replace_one(struct vy_env *env, struct vy_tx *tx, struct space *space,
-	       struct request *request, struct txn_stmt *stmt)
-{
-	(void)env;
-	assert(tx != NULL && tx->state == VINYL_TX_READY);
-	struct vy_lsm *pk = vy_lsm(space->index[0]);
-	assert(pk->index_id == 0);
-	if (tuple_validate_raw(pk->mem_format, request->tuple))
-		return -1;
-	struct tuple *new_tuple =
-		vy_stmt_new_replace(pk->mem_format, request->tuple,
-				    request->tuple_end);
-	if (new_tuple == NULL)
-		return -1;
-	/**
-	 * If the space has triggers, then we need to fetch the
-	 * old tuple to pass it to the trigger.
-	 */
-	if (stmt != NULL && !rlist_empty(&space->on_replace)) {
-		if (vy_get(pk, tx, vy_tx_read_view(tx),
-			   new_tuple, &stmt->old_tuple) != 0)
-			goto error_unref;
-	}
-	if (vy_tx_set(tx, pk, new_tuple))
-		goto error_unref;
-
-	if (stmt != NULL)
-		stmt->new_tuple = new_tuple;
-	else
-		tuple_unref(new_tuple);
-	return 0;
-
-error_unref:
-	tuple_unref(new_tuple);
-	return -1;
-}
-
-/**
- * Execute REPLACE in a space with multiple indexes and lookup for
- * an old tuple, that should has been set in \p stmt->old_tuple if
- * the space has at least one on_replace trigger.
- * @param env     Vinyl environment.
- * @param tx      Current transaction.
- * @param space   Vinyl space.
- * @param request Request with the tuple data.
- * @param stmt    Statement for triggers filled with old
- *                statement.
- *
- * @retval  0 Success
- * @retval -1 Memory error OR duplicate key error OR the primary
- *            index is not found OR a tuple reference increment
- *            error.
- */
-static inline int
-vy_replace_impl(struct vy_env *env, struct vy_tx *tx, struct space *space,
-		struct request *request, struct txn_stmt *stmt)
-{
-	assert(tx != NULL && tx->state == VINYL_TX_READY);
-	struct tuple *old_stmt = NULL;
-	struct tuple *new_stmt = NULL;
-	struct tuple *delete = NULL;
-	struct vy_lsm *pk = vy_lsm_find(space, 0);
-	if (pk == NULL) /* space has no primary key */
-		return -1;
-	/* Primary key is dumped last. */
-	assert(!vy_is_committed_one(env, pk));
-	assert(pk->index_id == 0);
-	if (tuple_validate_raw(pk->mem_format, request->tuple))
-		return -1;
-	new_stmt = vy_stmt_new_replace(pk->mem_format, request->tuple,
-				       request->tuple_end);
-	if (new_stmt == NULL)
-		return -1;
-
-	/* Get full tuple from the primary index. */
-	if (vy_get(pk, tx, vy_tx_read_view(tx), new_stmt, &old_stmt) != 0)
-		goto error;
-
-	if (old_stmt == NULL) {
-		/*
-		 * We can turn REPLACE into INSERT if the new key
-		 * does not have history.
-		 */
-		vy_stmt_set_type(new_stmt, IPROTO_INSERT);
-	}
-
-	/*
-	 * Replace in the primary index without explicit deletion
-	 * of the old tuple.
-	 */
-	if (vy_tx_set(tx, pk, new_stmt) != 0)
-		goto error;
-
-	if (space->index_count > 1 && old_stmt != NULL) {
-		delete = vy_stmt_new_surrogate_delete(pk->mem_format, old_stmt);
-		if (delete == NULL)
-			goto error;
-	}
-
-	/* Update secondary keys, avoid duplicates. */
-	for (uint32_t iid = 1; iid < space->index_count; ++iid) {
-		struct vy_lsm *lsm = vy_lsm(space->index[iid]);
-		if (vy_is_committed_one(env, lsm))
-			continue;
-		/*
-		 * Delete goes first, so if old and new keys
-		 * fully match, there is no look up beyond the
-		 * transaction index.
-		 */
-		if (old_stmt != NULL) {
-			if (vy_tx_set(tx, lsm, delete) != 0)
-				goto error;
-		}
-		if (vy_insert_secondary(env, tx, space, lsm, new_stmt) != 0)
-			goto error;
-	}
-	if (delete != NULL)
-		tuple_unref(delete);
-	/*
-	 * The old tuple is used if there is an on_replace
-	 * trigger.
-	 */
-	if (stmt != NULL) {
-		stmt->new_tuple = new_stmt;
-		stmt->old_tuple = old_stmt;
-	}
-	return 0;
-error:
-	if (delete != NULL)
-		tuple_unref(delete);
-	if (old_stmt != NULL)
-		tuple_unref(old_stmt);
-	if (new_stmt != NULL)
-		tuple_unref(new_stmt);
-	return -1;
-}
-
-/**
  * Check that the key can be used for search in a unique index
  * LSM tree.
  * @param  lsm        LSM tree for checking.
@@ -2316,18 +2162,86 @@ static int
 vy_replace(struct vy_env *env, struct vy_tx *tx, struct txn_stmt *stmt,
 	   struct space *space, struct request *request)
 {
+	assert(tx != NULL && tx->state == VINYL_TX_READY);
 	if (vy_is_committed(env, space))
 		return 0;
 	if (request->type == IPROTO_INSERT)
 		return vy_insert(env, tx, stmt, space, request);
 
-	if (space->index_count == 1) {
-		/* Replace in a space with a single index. */
-		return vy_replace_one(env, tx, space, request, stmt);
-	} else {
-		/* Replace in a space with secondary indexes. */
-		return vy_replace_impl(env, tx, space, request, stmt);
+	struct vy_lsm *pk = vy_lsm_find(space, 0);
+	if (pk == NULL)
+		return -1;
+	/* Primary key is dumped last. */
+	assert(!vy_is_committed_one(env, pk));
+
+	/* Validate and create a statement for the new tuple. */
+	if (tuple_validate_raw(pk->mem_format, request->tuple))
+		return -1;
+	stmt->new_tuple = vy_stmt_new_replace(pk->mem_format, request->tuple,
+					      request->tuple_end);
+	if (stmt->new_tuple == NULL)
+		return -1;
+	/*
+	 * Get the overwritten tuple from the primary index if
+	 * the space has on_replace triggers, in which case we
+	 * need to pass the old tuple to trigger callbacks, or
+	 * if the space has secondary indexes and so we need
+	 * the old tuple to delete it from them.
+	 */
+	if (space->index_count > 1 || !rlist_empty(&space->on_replace)) {
+		if (vy_get(pk, tx, vy_tx_read_view(tx),
+			   stmt->new_tuple, &stmt->old_tuple) != 0)
+			return -1;
+		if (stmt->old_tuple == NULL) {
+			/*
+			 * We can turn REPLACE into INSERT if the
+			 * new key does not have history.
+			 */
+			vy_stmt_set_type(stmt->new_tuple, IPROTO_INSERT);
+		}
+	}
+	/*
+	 * Replace in the primary index without explicit deletion
+	 * of the old tuple.
+	 */
+	if (vy_tx_set(tx, pk, stmt->new_tuple) != 0)
+		return -1;
+	if (space->index_count == 1)
+		return 0;
+	/*
+	 * Replace in secondary indexes with explicit deletion
+	 * of the old tuple, if any.
+	 */
+	int rc = 0;
+	struct tuple *delete = NULL;
+	if (stmt->old_tuple != NULL) {
+		delete = vy_stmt_new_surrogate_delete(pk->mem_format,
+						      stmt->old_tuple);
+		if (delete == NULL)
+			return -1;
+	}
+	for (uint32_t i = 1; i < space->index_count; i++) {
+		struct vy_lsm *lsm = vy_lsm(space->index[i]);
+		if (vy_is_committed_one(env, lsm))
+			continue;
+		/*
+		 * DELETE goes first, so if old and new keys
+		 * fully match, there is no look up beyond the
+		 * transaction write set.
+		 */
+		if (delete != NULL) {
+			rc = vy_tx_set(tx, lsm, delete);
+			if (rc != 0)
+				break;
+		}
+		rc = vy_insert_secondary(env, tx, space, lsm,
+					 stmt->new_tuple);
+		if (rc != 0)
+			break;
 	}
+	if (delete != NULL)
+		tuple_unref(delete);
+	return rc;
 }
 
 static int