fix: Fix connection slot leak when context is cancelled during acquire#1759
Merged
kavirajk merged 10 commits intoClickHouse:mainfrom Mar 4, 2026
Merged
fix: Fix connection slot leak when context is cancelled during acquire#1759kavirajk merged 10 commits intoClickHouse:mainfrom
kavirajk merged 10 commits intoClickHouse:mainfrom
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kavirajk
reviewed
Feb 3, 2026
tests/context_cancel_test.go
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| // eventually exhaust the connection pool. | ||
| func TestContextCancellationNoConnectionSlotLeak(t *testing.T) { | ||
| TestProtocols(t, func(t *testing.T, protocol clickhouse.Protocol) { | ||
| SkipOnHTTP(t, protocol, "context cancel slot leak test") |
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I wonder, why do we skip on this on HTTP? both TCP and HTTP uses pooling via these acquire() api.
Signed-off-by: Kaviraj <kavirajkanagaraj@gmail.com>
Signed-off-by: Kaviraj <kavirajkanagaraj@gmail.com>
Signed-off-by: Kaviraj <kavirajkanagaraj@gmail.com>
in dial_http, we modify the passed in options in-plce. Which restricts (and cause data race) when end up using multiple go-routines This PR uses just the local copy of the options's compression and scheme during dial_http Signed-off-by: Kaviraj <kavirajkanagaraj@gmail.com>
kavirajk
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Mar 4, 2026
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Fixes a connection pool leak that happens when a query context is cancelled while acquiring a connection. When
acquire()gets a connection slot from thech.openchannel but thench.idle.Get(ctx)returns a context cancellation error, we were returning immediately without releasing that slot. After enough cancelled queries, the pool would be exhausted even though connections were available.This fix makes sure the slot gets released. It also adds a test that reproduces the previous issue and shows that is now fixed.