Stabilize portals regression test against synchronize_seqscans (v16)#928
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bayandin wants to merge 1 commit intoREL_16_STABLE_neonfrom
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Stabilize portals regression test against synchronize_seqscans (v16)#928bayandin wants to merge 1 commit intoREL_16_STABLE_neonfrom
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Problem
The
portalspg_regress test declares cursors ontenk2withoutORDER BY, relying on heap scan order for expected output. Whensynchronize_seqscansis on (the default) and another backend in the same parallel group is concurrently scanningtenk2, the new scan can start mid-table, producing rows in a different order than the.outfile expects.The issue surfaces more on slower storages (for example network-attached), where scan timing differences widen the window for concurrent scan synchronization.
Summary of changes
SET synchronize_seqscans = off;at the top ofportals.sqlandRESET synchronize_seqscans;at the end