Date: Tue, 29 Aug 2006 16:10:56 +0100
From: "Jignesh K. Shah" <J.K.Shah@Sun.COM>
Subject: Re: slow i/o
In-reply-to: <8d04ce990608281606r153ed796xcf5d9d3a44d8e632@mail.gmail.com>
To: Junaili Lie <junaili@gmail.com>
Cc: pgsql-performance@postgresql.org
Message-id: <44F45900.4000702@sun.com>
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Also to answer your real question:

DTrace On Solaris 10:

# dtrace -s /usr/demo/dtrace/whoio.d

It will tell you the pids doing the io activity and  on which devices.
There are more scripts in that directory like iosnoop.d, iotime.d and others which also will give 
other details like file accessed, time it took for the io etc.

Hope this helps.

Regards,
Jignesh


Junaili Lie wrote:
> Hi everyone,
> We have a postgresql 8.1 installed on Solaris 10. It is running fine. 
> However, for the past couple days, we have seen the i/o reports 
> indicating that the i/o is busy most of the time. Before this, we only 
> saw i/o being busy occasionally (very rare). So far, there has been no 
> performance complaints by customers, and the slow query reports doesn't 
> indicate anything out of the ordinary.
> There's no code changes on the applications layer and no database 
> configuration changes.
> I am wondering if there's a tool out there on Solaris to tell which 
> process is doing most of the i/o activity?
> Thank you in advance.
> 
> J
>