Ocfs2 users - Feb 2008 - Anyone have an idea how to find file i/o throughput?

We got a remote Oracle 10g R2 standby running on OCFS2. Initial when we
started the standby, read I/O was < 5MB/sec on average. Since then it
has grown to over 40MB/sec (longer average, it peaks much higher). Here
is a graph showing this:

http://www.alameda.net/~ulf/dbphx01.png

We also have a local standby running (on EXT3) which is not showing the
same symptom. I am trying to find where all these reads are happening.
Anyone have an idea how to figure that out on Linux?

Ulf.

If a userspace process is behind the io surge, then strace should help.
But determining the process may require a bit of trial and error.

Ulf Zimmermann wrote:
> We got a remote Oracle 10g R2 standby running on OCFS2. Initial when we
> started the standby, read I/O was < 5MB/sec on average. Since then it
> has grown to over 40MB/sec (longer average, it peaks much higher). Here
> is a graph showing this:
>
> http://www.alameda.net/~ulf/dbphx01.png
>
> We also have a local standby running (on EXT3) which is not showing the
> same symptom. I am trying to find where all these reads are happening.
> Anyone have an idea how to figure that out on Linux?
>
> Ulf.
>
>
> _______________________________________________
> Ocfs2-users mailing list
> Ocfs2-users@oss.oracle.com
> http://oss.oracle.com/mailman/listinfo/ocfs2-users
>

Forgot to mention, this remote server is just Oracle. It has one standby
database and one local database, the local one is suppose to be idle,
i.e. nothing connecting to it, besides once in a while for available
check.

While the primary database of the standby was down, I saw less disk read
access, but every 5 minutes for about 60 seconds I would see
50-60MB/sec. After the primary came back up, read access is as high as
160MB/sec.

We are only seeing it on this single node of the remote standby. The
local standby (on EXT3) is not doing the same thing.
> -----Original Message-----
> From: Sunil Mushran [mailto:sunil.mushran@oracle.com]
> Sent: Monday, February 18, 2008 19:28
> To: Ulf Zimmermann
> Cc: ocfs2-users@oss.oracle.com
> Subject: Re: [Ocfs2-users] Anyone have an idea how to find file i/o
> throughput?
> 
> If a userspace process is behind the io surge, then strace should
help.
> But determining the process may require a bit of trial and error.
> 
> Ulf Zimmermann wrote:
> > We got a remote Oracle 10g R2 standby running on OCFS2. Initial when
we
> > started the standby, read I/O was < 5MB/sec on average. Since then
it
> > has grown to over 40MB/sec (longer average, it peaks much higher).
Here
> > is a graph showing this:
> >
> > http://www.alameda.net/~ulf/dbphx01.png
> >
> > We also have a local standby running (on EXT3) which is not showing
the
> > same symptom. I am trying to find where all these reads are
happening.
> > Anyone have an idea how to figure that out on Linux?
> >
> > Ulf.
> >
> >
> > _______________________________________________
> > Ocfs2-users mailing list
> > Ocfs2-users@oss.oracle.com
> > http://oss.oracle.com/mailman/listinfo/ocfs2-users
> >