Fix deadlock when fetching next chunk (1.3)#266
Merged
staticlibs merged 1 commit intoduckdb:v1.3-ossivalisfrom Jun 15, 2025
Merged
Fix deadlock when fetching next chunk (1.3)#266staticlibs merged 1 commit intoduckdb:v1.3-ossivalisfrom
staticlibs merged 1 commit intoduckdb:v1.3-ossivalisfrom
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This is a backport of the PR duckdb#242 to `v1.3-ossivalis` stable branch. When connection is being closed, it closes all statements and all result sets on these statements. All this is done while holding connection lock. When fetching next chunk, result set needs to take both result set and connection locks. Because of the wrong order of taking these locks, concurrent `close()` call on result set, initiated from `Connection#close()` was causing a deadlock. This change reorders locks in `ResultSet#fetchChunk()` to fix this. Testing: new test added that reproduces the deadlock reliably (may need to raise the number of iterations). Fixes: duckdb#241
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This is a backport of the PR #242 to
v1.3-ossivalisstable branch.When connection is being closed, it closes all statements and all result sets on these statements. All this is done while holding connection lock.
When fetching next chunk, result set needs to take both result set and connection locks. Because of the wrong order of taking these locks, concurrent
close()call on result set, initiated fromConnection#close()was causing a deadlock.This change reorders locks in
ResultSet#fetchChunk()to fix this.Testing: new test added that reproduces the deadlock reliably (may need to raise the number of iterations).
Fixes: #241