sys.dm_tran_top_version_generators reads the whole version store. It ran
every 5 minutes while the version store was over half the threshold,
i.e. exactly when it is large and expensive to scan, and a timeout failed
the whole tempdb collection. It now runs at most once per hour (the
previous answer is kept in between, with its time) and a failed scan
keeps the previous answer.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
A five-minute collector reads tempdb space (free, version store, user and
internal objects, whether files can grow), the 'Version Store Size (KB)'
counter, the sessions using most tempdb, the oldest snapshot transaction
and, only when the version store is large, the databases generating
versions. Trend and heavy sessions survive restarts; used space and the
version store become metrics with explanation and assessment.
Rules SQLI-TEMP-001 (version store > 1 GB or steadily growing),
SQLI-TEMP-002 (nearly full and cannot grow) and SQLI-TEMP-003 (session
above 1 GB for 15 minutes), configurable under SQLInsight:Tempdb.
"tempdb lige nu" on the instance page; GET /api/v1/instances/{name}/tempdb.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>