2011-02-07 17:09:28

by Ozan Çağlayan

Subject: A lot of [ext4-dio-unwrit] threads around

Hi,


This is 2.6.35.11 on a 24-core HP Proliant server with 8 mounted ext4
filesystems. There are 7 LXC containers which does heavy compiling
workload during the day.

Uptime is 3 days and currently there are 216 ext4-dio-unwrit threads in
ps aux output? Is it normal or a symptom of a problem?

Thanks
--
Pardus Linux
http://www.pardus.org.tr/eng

2011-02-07 18:05:33

by Theodore Ts'o

Subject: Re: A lot of [ext4-dio-unwrit] threads around

On Mon, Feb 07, 2011 at 07:09:26PM +0200, Ozan Çağlayan wrote:
>
> This is 2.6.35.11 on a 24-core HP Proliant server with 8 mounted
> ext4 filesystems. There are 7 LXC containers which does heavy
> compiling workload during the day.
>
> Uptime is 3 days and currently there are 216 ext4-dio-unwrit threads
> in ps aux output? Is it normal or a symptom of a problem?

It's normal; the workqueues are created statically at mount time, one
per cpu per file system. There are some plans in train for a more
efficient way of dealing with workqueues in general on systems with
large numbers of CPU's, but for 2.6.35, yes, that's normal.

- Ted