sqle: skip dolt commit path for read-only transactions#10686
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DreadPirateRobertz wants to merge 1 commit intodolthub:mainfrom
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sqle: skip dolt commit path for read-only transactions#10686DreadPirateRobertz wants to merge 1 commit intodolthub:mainfrom
DreadPirateRobertz wants to merge 1 commit intodolthub:mainfrom
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When dolt_transaction_commit=true, every transaction close—including read-only SELECTs—runs PendingCommitAllStaged which stages all tables and checks for changes. For read-only queries there are never changes, so this work is wasted: StageAllTables runs, newPendingCommit returns nil, and the code falls through to commitWorkingSet anyway. In high-frequency read workloads (e.g. 6 agents polling every 30s), this overhead compounds to 100k+ empty commit attempts and 700k+ connections over hours, eventually overwhelming the server. Short-circuit by checking DoltTransaction.IsReadOnly() before entering the dolt commit path. Read-only transactions go directly to commitWorkingSet, matching the behavior they would have gotten anyway but without the staging overhead. Fixes dolthub#10685 Co-Authored-By: Claude Opus 4.6 <[email protected]>
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Thanks for the contribution. I've kicked off the test suite. This seems ok at first glance. Could probably use a test. |
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Summary
PendingCommitAllStagedpath for read-only transactions whendolt_transaction_commit=truecommitWorkingSet, matching the behavior they'd get anyway but without staging overheadProblem
When
dolt_transaction_commit=true, every transaction close—including read-only SELECTs—runsPendingCommitAllStagedwhich callsStageAllTablesandnewPendingCommit. For read-only queries there are never changes to stage, sopendingCommitalways returns nil and the code falls through tocommitWorkingSetanyway.In production with 6 agents polling every 30 seconds, we observed:
database not founderrors then crashingFix
Check
DoltTransaction.IsReadOnly()before entering the dolt commit path. TheIsReadOnly()method already exists onDoltTransactionand checkstx.tCharacteristic == sql.ReadOnly. Read-only transactions short-circuit directly tocommitWorkingSet.Test plan
TestDoltTransactionCommitOneClientand related tests pass (write transactions still commit)dolt_transaction_commit=1no longer triggerPendingCommitAllStagedFixes #10685
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