Hi, On 2014-05-07 10:21:26 -0700, Jeff Janes wrote: > On Wed, May 7, 2014 at 12:48 AM, Andres Freund <and...@2ndquadrant.com>wrote: > > > Hi, > > > > On 2014-05-07 00:35:35 -0700, Jeff Janes wrote: > > > When recovering from a crash (with injection of a partial page write at > > > time of crash) against 7c7b1f4ae5ea3b1b113682d4d I get a checksum > > > verification failure. > > > > > > 16396 is a gin index. > > > > Over which type? What was the load? make check? > > > > A gin index on text[]. > > The load is a variation of the crash recovery tester I've been using the > last few years, this time adapted to use a gin index in a rather unnatural > way. I just increment a counter on a random row repeatedly via a unique > key, but for this purpose that unique key is stuffed into text[] along with > a bunch of cruft. The cruft is text representations of negative integers, > the actual key is text representation of nonnegative integers. > > The test harness (patch to induce crashes, and two driving programs) and a > preserved data directory are here: > > https://drive.google.com/folderview?id=0Bzqrh1SO9FcESDZVeFk5djJaeHM&usp=sharing > > (role jjanes, database jjanes) > > As far as I can tell, this problem goes back to the beginning of page > checksums.
Interesting. > > > If I have it ignore checksum failures, there is no apparent misbehavior. > > > I'm trying to bisect it, but it could take a while and I thought someone > > > might have some theories based on the log: > > > > If you have the WAL a pg_xlogdump grepping for everything referring to > > that block would be helpful. > > > > The only record which mentions block 28486 by name is this one: Hm, try running it with -b specified. > rmgr: Gin len (rec/tot): 1576/ 1608, tx: 77882205, lsn: > 11/30F4C2C0, prev 11/30F4C290, bkp: 0000, desc: Insert new list page, node: > 1663/16384/16396 blkno: 28486 > > However, I think that that record precedes the recovery start point. If that's the case it seems likely that a PageSetLSN() or PageSetDirty() are missing somewhere... Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
