Обсуждение: pg_stat_statements behavior in crash recovery
Hello,
I understand that when the pg_stat_statements.save=true the statement statistics are saved at global/pg_stat_statements.stat. This file is read on next startup and then deleted.
If there is a crash i understand that pg_stat_statements.stat file is not created even if pg_stat_statements.save=true.
If the crash happened before pg_stat_statements.stat file is deleted then, on recovery, is that pg_stat_statements.stat file deleted?
On crash recovery, are statement statistics reset ,to same values as would be the case on normal startup in the case pg_stat_statements.save=false?
Thank you
Sameer
On Wed, Jun 19, 2013 at 5:32 AM, Sameer Thakur <samthakur74@gmail.com> wrote: > If there is a crash i understand that pg_stat_statements.stat file is not > created even if pg_stat_statements.save=true. > If the crash happened before pg_stat_statements.stat file is deleted then, > on recovery, is that pg_stat_statements.stat file deleted? > On crash recovery, are statement statistics reset ,to same values as would > be the case on normal startup in the case pg_stat_statements.save=false? The pg_stat_statements statistics file is just deleted when the server starts, and statistics are serialized to disk when there's a clean shutdown. pg_stat_statements is similar to the statistics collector here. Why are you posting this to the -performance list? -- Regards, Peter Geoghegan
>Why are you posting this to the -performance list?
Sorry, maybe -general was the correct place. I thought that pg_stat_statements was a performance diagnostics tool, so -performance was the correct forum
Thank you
Sameer