On 02/01/2014 05:28 AM, Bruce Momjian wrote: > On Fri, Aug 2, 2013 at 04:00:03PM +0800, Craig Ringer wrote: >> FOR SHARE|UPDATE NOWAIT will still block if they have to follow a ctid >> chain because the call to EvalPlanQualFetch doesn't take a param for >> noWait, so it doesn't know not to block if the updated row can't be locked. >> >> The attached patch against master includes an isolationtester spec to >> demonstrate this issue and a proposed fix. Builds with the fix applied >> pass "make check" and isolationtester "make installcheck". >> >> To reach this point you need to apply the patch in >> http://www.postgresql.org/message-id/51fb4305.3070...@2ndquadrant.com >> first, otherwise you'll get stuck there and won't touch the code changed >> in this patch. > > The above looks like a legitimate patch that was not applied: > > http://www.postgresql.org/message-id/51fb6703.9090...@2ndquadrant.com > > The patch mentioned in the text above was applied, I think.
The first patch, linked to in text, was commited as 706f9dd914c64a41e06b5fbfd62d6d6dab43eeb8. I can't see the second in the history either. It'd be good to get it committed, though the issue is obviously not causing any great outcry. It was detected when testing a high-rate queueing system in PostgreSQL. -- Craig Ringer 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
