[PATCH] vinyl: fail transaction immediately if it does not fit in memory

[PATCH] vinyl: fail transaction immediately if it does not fit in memory

[Vladimir Davydov]

If the size of a transaction is greater than the configured memory
limit (box.cfg.vinyl_memory), the transaction will hang on commit
for 60 seconds (box.cfg.vinyl_timeout) and then fail with the
following error message:

  Timed out waiting for Vinyl memory quota

This is confusing. Let's fail such transactions immediately with
OutOfMemory error.

Closes #3291
---
https://github.com/tarantool/tarantool/issues/3291
https://github.com/tarantool/tarantool/commits/gh-3291-vy-fail-huge-tx-early

 src/box/vinyl.c                   | 10 +++++++
 test/vinyl/quota_timeout.result   | 55 ++++++++++++++++++++++++++-------------
 test/vinyl/quota_timeout.test.lua | 34 +++++++++++++++---------
 3 files changed, 68 insertions(+), 31 deletions(-)

diff --git a/src/box/vinyl.c b/src/box/vinyl.c
index 8abfaac9..d2cd61f0 100644
--- a/src/box/vinyl.c
+++ b/src/box/vinyl.c
@@ -2325,6 +2325,16 @@ vinyl_engine_prepare(struct engine *engine, struct txn *txn)
 		return -1;
 
 	/*
+	 * The configured memory limit will never allow us to commit
+	 * this transaction. Fail early.
+	 */
+	if (tx->write_size > env->quota.limit) {
+		diag_set(OutOfMemory, tx->write_size,
+			 "lsregion", "vinyl transaction");
+		return -1;
+	}
+
+	/*
 	 * Do not abort join/subscribe on quota timeout - replication
 	 * is asynchronous anyway and there's box.info.replication
 	 * available for the admin to track the lag so let the applier
diff --git a/test/vinyl/quota_timeout.result b/test/vinyl/quota_timeout.result
index 1e66d392..e4bced02 100644
--- a/test/vinyl/quota_timeout.result
+++ b/test/vinyl/quota_timeout.result
@@ -108,7 +108,7 @@ box.error.injection.set('ERRINJ_VY_RUN_WRITE_TIMEOUT', 0)
 ---
 - ok
 ...
-s:drop()
+s:truncate()
 ---
 ...
 box.snapshot()
@@ -116,11 +116,36 @@ box.snapshot()
 - ok
 ...
 --
--- Check that exceeding quota triggers dump of all spaces.
+-- Check that exceeding quota doesn't hang the scheduler
+-- in case there's nothing to dump.
 --
-box.cfg{vinyl_timeout=0.01}
+-- The following operation should fail instantly irrespective
+-- of the value of 'vinyl_timeout' (gh-3291).
+--
+box.info.vinyl().quota.used == 0
+---
+- true
+...
+box.cfg{vinyl_timeout = 9000}
+---
+...
+pad = string.rep('x', box.cfg.vinyl_memory)
+---
+...
+_ = s:auto_increment{pad}
+---
+- error: Failed to allocate 1048615 bytes in lsregion for vinyl transaction
+...
+s:drop()
+---
+...
+box.snapshot()
 ---
+- ok
 ...
+--
+-- Check that exceeding quota triggers dump of all spaces.
+--
 s1 = box.schema.space.create('test1', {engine = 'vinyl'})
 ---
 ...
@@ -133,34 +158,28 @@ s2 = box.schema.space.create('test2', {engine = 'vinyl'})
 _ = s2:create_index('pk')
 ---
 ...
-_ = s1:auto_increment{}
+pad = string.rep('x', 64)
 ---
 ...
-box.info.vinyl().quota.used
+_ = s1:auto_increment{pad}
 ---
-- 49186
 ...
-pad = string.rep('x', box.cfg.vinyl_memory)
+s1.index.pk:info().memory.bytes > 0
 ---
+- true
 ...
-_ = s2:auto_increment{pad}
+pad = string.rep('x', box.cfg.vinyl_memory - string.len(pad))
 ---
-- error: Timed out waiting for Vinyl memory quota
 ...
-while box.info.vinyl().quota.used > 0 do fiber.sleep(0.01) end
+_ = s2:auto_increment{pad}
 ---
 ...
-box.info.vinyl().quota.used
+while s1.index.pk:info().disk.dump.count == 0 do fiber.sleep(0.01) end
 ---
-- 0
 ...
---
--- Check that exceeding quota doesn't hang the scheduler
--- in case there's nothing to dump.
---
-s2:auto_increment{pad}
+s1.index.pk:info().memory.bytes == 0
 ---
-- error: Timed out waiting for Vinyl memory quota
+- true
 ...
 test_run:cmd('switch default')
 ---
diff --git a/test/vinyl/quota_timeout.test.lua b/test/vinyl/quota_timeout.test.lua
index ed5ba79d..c3d17b44 100644
--- a/test/vinyl/quota_timeout.test.lua
+++ b/test/vinyl/quota_timeout.test.lua
@@ -50,33 +50,41 @@ test_run:cmd("clear filter")
 
 box.error.injection.set('ERRINJ_VY_RUN_WRITE_TIMEOUT', 0)
 
+s:truncate()
+box.snapshot()
+
+--
+-- Check that exceeding quota doesn't hang the scheduler
+-- in case there's nothing to dump.
+--
+-- The following operation should fail instantly irrespective
+-- of the value of 'vinyl_timeout' (gh-3291).
+--
+box.info.vinyl().quota.used == 0
+box.cfg{vinyl_timeout = 9000}
+pad = string.rep('x', box.cfg.vinyl_memory)
+_ = s:auto_increment{pad}
+
 s:drop()
 box.snapshot()
 
 --
 -- Check that exceeding quota triggers dump of all spaces.
 --
-box.cfg{vinyl_timeout=0.01}
-
 s1 = box.schema.space.create('test1', {engine = 'vinyl'})
 _ = s1:create_index('pk')
 s2 = box.schema.space.create('test2', {engine = 'vinyl'})
 _ = s2:create_index('pk')
 
-_ = s1:auto_increment{}
-box.info.vinyl().quota.used
+pad = string.rep('x', 64)
+_ = s1:auto_increment{pad}
+s1.index.pk:info().memory.bytes > 0
 
-pad = string.rep('x', box.cfg.vinyl_memory)
+pad = string.rep('x', box.cfg.vinyl_memory - string.len(pad))
 _ = s2:auto_increment{pad}
 
-while box.info.vinyl().quota.used > 0 do fiber.sleep(0.01) end
-box.info.vinyl().quota.used
-
---
--- Check that exceeding quota doesn't hang the scheduler
--- in case there's nothing to dump.
---
-s2:auto_increment{pad}
+while s1.index.pk:info().disk.dump.count == 0 do fiber.sleep(0.01) end
+s1.index.pk:info().memory.bytes == 0
 
 test_run:cmd('switch default')
 test_run:cmd("stop server test")
-- 
2.11.0