Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Simon Riggs
On Thu, 2010-05-13 at 20:13 +0900, Fujii Masao wrote: > On Thu, May 13, 2010 at 8:05 PM, Simon Riggs wrote: > > On Thu, 2010-05-13 at 19:32 +0900, Fujii Masao wrote: > >> On Thu, May 13, 2010 at 7:22 PM, Simon Riggs wrote: > >> > On Thu, 2010-05-13 at 19:08 +0900, Fujii Masao wrote: > >> > > >> >

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Simon Riggs
On Thu, 2010-05-13 at 20:13 +0900, Fujii Masao wrote: > On Thu, May 13, 2010 at 8:05 PM, Simon Riggs wrote: > > On Thu, 2010-05-13 at 19:32 +0900, Fujii Masao wrote: > >> On Thu, May 13, 2010 at 7:22 PM, Simon Riggs wrote: > >> > On Thu, 2010-05-13 at 19:08 +0900, Fujii Masao wrote: > >> > > >> >

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Fujii Masao
On Thu, May 13, 2010 at 8:05 PM, Simon Riggs wrote: > On Thu, 2010-05-13 at 19:32 +0900, Fujii Masao wrote: >> On Thu, May 13, 2010 at 7:22 PM, Simon Riggs wrote: >> > On Thu, 2010-05-13 at 19:08 +0900, Fujii Masao wrote: >> > >> >> I was able to reproduce such a hang by not executing another >>

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Simon Riggs
On Thu, 2010-05-13 at 19:32 +0900, Fujii Masao wrote: > On Thu, May 13, 2010 at 7:22 PM, Simon Riggs wrote: > > On Thu, 2010-05-13 at 19:08 +0900, Fujii Masao wrote: > > > >> I was able to reproduce such a hang by not executing another > >> transaction after rollback. In this case, walsender canno

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Fujii Masao
On Thu, May 13, 2010 at 7:22 PM, Simon Riggs wrote: > On Thu, 2010-05-13 at 19:08 +0900, Fujii Masao wrote: > >> I was able to reproduce such a hang by not executing another >> transaction after rollback. In this case, walsender cannot replicate >> the rollback since it's not in the disk. > > WALW

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Simon Riggs
On Thu, 2010-05-13 at 19:08 +0900, Fujii Masao wrote: > I was able to reproduce such a hang by not executing another > transaction after rollback. In this case, walsender cannot replicate > the rollback since it's not in the disk. WALWriter is not active? -- Simon Riggs www.2ndQuadra

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Fujii Masao
On Thu, May 13, 2010 at 6:47 PM, Simon Riggs wrote: > Rollbacks are always flushed to disk, so this explanation doesn't work. > Even if it were it would take no longer than ~1 sec if everything were > working correctly on the test system. Yeah, rollbacks are always flushed sooner or later, but no

Re: [HACKERS] weird hang while running in HS mode

2010-05-13 Thread Simon Riggs
On Thu, 2010-05-13 at 10:49 +0900, Fujii Masao wrote: > On Thu, May 13, 2010 at 3:50 AM, Robert Haas wrote: > > rhaas=# rollback; > > ROLLBACK > > > > So at this point, one would think that there are no locks hanging > > around anywhere. Back to the standby: > > > > rhaas=# select * from pgbench_

Re: [HACKERS] weird hang while running in HS mode

2010-05-12 Thread Fujii Masao
On Thu, May 13, 2010 at 3:50 AM, Robert Haas wrote: > rhaas=# rollback; > ROLLBACK > > So at this point, one would think that there are no locks hanging > around anywhere.  Back to the standby: > > rhaas=# select * from pgbench_accounts; > I think that this problem happens because the WAL record

[HACKERS] weird hang while running in HS mode

2010-05-12 Thread Robert Haas
While fooling around with Hot Standby today, I did this on the master: rhaas=# begin work; BEGIN rhaas=# lock table pgbench_accounts; LOCK TABLE Then on slave I did this: rhaas=# select * from pgbench_accounts; ERROR: canceling statement due to conflict with recovery DETAIL: User query might h