release-26.2: descs: evict stale SystemDatabaseCache entries on descriptor-not-found#169389
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trunk-io[bot] merged 1 commit intoApr 30, 2026
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PR cockroachdb#169044 allowed SystemDatabaseCache to accept updated name→ID mappings, but the update path was never triggered because the stale cache hit in lookupDescriptorID prevented the KV read that would have provided the corrected mapping — a self-reinforcing cycle. When getDescriptorByName resolves a system table name to an ID but the descriptor at that ID doesn't exist, evict the entry from the SystemDatabaseCache. The next lookup misses the cache, reads from KV, and self-heals. Fixes cockroachdb#169316 Release note (bug fix): Fixed a bug where PCR reader tenants could permanently fail authentication after SetupOrAdvanceStandbyReaderCatalog rewrote the system.privileges namespace entry. A stale cached name→ID mapping was never refreshed, causing every SQL connection to fail with "descriptor not found". Co-Authored-By: roachdev-claude <roachdev-claude-bot@cockroachlabs.com>
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Reviewable status:complete! 1 of 0 LGTMs obtained (waiting on spilchen).
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Backport 1/1 commits from #169351 on behalf of @msbutler.
Summary
PR #169044 allowed
SystemDatabaseCacheto accept updated name→ID mappings,but the update path was never triggered because the stale cache hit in
lookupDescriptorIDprevented the KV read that would have provided thecorrected mapping — a self-reinforcing cycle.
When
getDescriptorByNameresolves a system table name to an ID but thedescriptor at that ID doesn't exist, evict the entry from the
SystemDatabaseCache. The next lookup misses the cache, reads from KV, andself-heals. This works across all nodes since the corrected namespace entry
is in shared KV storage.
Fixes #169316
Epic: none
Release note (bug fix): Fixed a bug where PCR reader tenants could
permanently fail authentication after
SetupOrAdvanceStandbyReaderCatalogrewrote the
system.privilegesnamespace entry. A stale cached name→IDmapping was never refreshed, causing every SQL connection to fail with
"descriptor not found".
Release justification: