Re: ext2/3 files per directory limits

[Joel Jaeggli]

On Wed, 23 Feb 2005, Ron Peterson wrote:

> I would like to better understand ext2/3's performance characteristics.
>
> I'm specifically interested in how ext2/3 will handle a /var/spool/mail
> directory w/ ~6000 mbox format inboxes, handling approx 1GB delivered as
> 75,000 messages daily.  Virtually all access is via imap, w/ approx
> ~1000 imapd processes running during peak load.  Local delivery is via
> procmail, which by default uses both kernel-supported locking calls and
> .lock files.

At some point it makes sense to subdivide you mail load because 
serialization of i/o on that one filesystem becomes a bigger issue than 
the performance of your filesystem... We deliver into mbox formatted 
mailboxes inside users homedirs, some folks do a similar thing with 
maildir. In the end you can on make one filesystem so fast. beyond that 
you need more filesystems to acheive any kind of reasonable scaling...

> I understand that various tuning parameters will have an impact,
> e.g. putting the journal on a separate device, setting the noatime mount
> option, etc.  I also understand that there are other mailbox formats and
> other strategies for locating mail spools (e.g. in user's home
> directories).
>
> I'm interested in people's thoughts on these issues, but I'm mostly
> interested in whether or not the scenario I described falls within
> ext2/3's designed capabilities.
>
> Best.

--
-------------------------------------------------------------------------- 
Joel Jaeggli  	       Unix Consulting 	       joelja@xxxxxxxxxxxxxxxxxxxx 
GPG Key Fingerprint:     5C6E 0104 BAF0 40B0 5BD3 C38B F000 35AB B67F 56B2

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/