On Wed, Jan 25, 2017 at 7:14 PM, Michael Paquier <michael.paqu...@gmail.com> wrote: > (Adding Robert in CC.) > > On Thu, Jan 26, 2017 at 4:34 AM, Wang Hao <whbe...@gmail.com> wrote: >> An unlogged table has an initialization fork. The initialization fork does >> not have an BM_PERMANENT flag when get a buffer. >> In checkpoint (not shutdown or end of recovery), it will not write to disk. >> after a crash recovery, the page of initialization fork will not correctly, >> then make the main fork not correctly too. > > For init forks the flush need absolutely to happen, so that's really > not good. We ought to fix BufferAlloc() appropriately here.
I agree with that, but I propose the attached version instead. It seems cleaner to have the entire test for setting BM_PERMANENT in one place rather than splitting it up as you did. I believe this sets a record for the longest-lived data corruption bug in a commit made by me. Six years and change, woohoo. :-( -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
unlogged-flush-fix-rmh.patch
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