Re: BUG #12071: Stat collector went crasy (50MB/s constant writes)

On Wed, Nov 26, 2014 at 4:15 PM, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
wrote:

> maxim(dot)boguk(at)gmail(dot)com wrote:
>
> > Hi,
> >
> > On one of my servers stat collector went crasy on idle system.
> > It constantly write around 50MB/s on idle database (no activity at all).
> >
> > What I tried:
> > 1)stop/start the database - no effect
> > 2)update to 9.2.9 from 9.2.7 - no effect
>
> Is the server time correct? What is autovacuum doing

Server time look correct for me.
Аutovacuum doing nothing since no activity on server at all (I checked it
twice).

After careful examination of strace output I found one strange thing:
constant flow of:
16:22:33.202523 read(3, 0x7fff4148a5b0, 16) = -1 EAGAIN (Resource
temporarily unavailable)
16:22:33.297432 read(3, 0x7fff4148a5b0, 16) = -1 EAGAIN (Resource
temporarily unavailable)
16:22:33.322471 read(3, 0x7fff4148a5b0, 16) = -1 EAGAIN (Resource
temporarily unavailable)
16:22:33.417873 read(3, 0x7fff4148a5b0, 16) = -1 EAGAIN (Resource
temporarily unavailable)
16:22:33.456801 read(3, 0x7fff4148a5b0, 16) = -1 EAGAIN (Resource
temporarily unavailable)
But I not sure that is actual error signal or normal behaviour.

--
Maxim Boguk
Senior Postgresql DBA
http://www.postgresql-consulting.ru/ <http://www.postgresql-consulting.com/>