[Linux-cluster] GFS filesystem "hang" with cluster-1.03.00

[Josef Whiter]

On Fri, Oct 20, 2006 at 03:34:33PM +0200, Ramon van Alteren wrote:
> Yes, this was the previous exchange. In the same exchange I was advised 
> by Wendy Cheng to switch to iozone because it would avoid such multiple 
> lock calls (less stat on files) instead of bonnie++ which we were 
> previously testing with.
>

Ahh I mised that, apologies.
 
> My test-run last night started at 4AM with 4 different iozone processes 
> using a temp file in different directories on the same filesystem / 
> logical volume.
> 
> AFAIK this would avoid the problem you mention above ?
> 
> All iozone processes were in D (uninteruptable sleep) by the time I woke 
> up and had a look 8AM this morning.
> 
> I would expect gfs to deal with this gracefully and return a performance 
> metric on multiple writes because:
> 
> * Not in same directory so no dir-lock to pass around
> * Different files
>

Ok if you are hitting this problem then the best thing to do is grab serveral
instances of sysrq-t from all nodes so we can see who/what is hanging and start
poking around.  Thank you,

Josef