On 2014-10-09 22:47:48 +0900, MauMau wrote: > Hello, > > One user reported a hang problem with 9.4 beta2 on Windows. The PostgreSQL > is 64-bit version. I couldn't find the cause, but want to solve the > problem. Could you help with this? > > I heard that the user had run 16 concurrent psql sessions which executes > INSERT and UPDATE statements, which is a write-intensive stress test. He > encountered the hang phenomenon twice, one of which occured several hours > after the start of the test, and the other occured about an hour after the > test launch. > > The user gave me the stack traces, which I attached at the end of this mail. > The problem appears to be related to the xlog insert scaling. But I can't > figure out where the root cause lies --- WAL slot handling, spinlock on > Windows, or PGSemaphoreLock/UnLock on Windows? > > The place I suspect is S_UNLOCK(). It doesn't use any memory barrier. Is > this correct on Intel64 processors?
What precisely do you mean with "Intel64"? 64bit x86 or Itanium? Also, what's the precise workload? Can you reproduce the problem? 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
