Re: XFS over NFS corruption

[Craig Tierney <ctierney@hpti.com>]

On Wed, 2004-06-09 at 11:49, Marat Mukhitov wrote:
> Andy ,
> 
> We had a similar problem. 
> Changing "async" to "sync" option of exportfs  on NFS server  helps in our case.
> 
> Regards,
> Marat 

Changing that option kills performance though.  Also, in my
case where I am getting corruption, switching to sync did
not help.

Craig

> 
> 
> On Wednesday 09 June 2004 18:54, Andy wrote:
> > I thought I had seen the bug even writing to an non-XFS nfs server, but I
> > can't absolutely confirm this at the time (I was not doing the testing at
> > the time, and some of the result may not have been accurate)
> >
> > But, the description of bug #198 on the XFS bugzilla, does sound like what
> > I am seeing.
> >
> > What I do in my tests is take a file of offsets (every group of 4 bytes
> > contains the offset of the 1st byte of the group) and copy that file to an
> > nfs mounted volume and then compare the local copy to the remote copy
> > (copying to several systems, each server is also receiving from several
> > systems).  After a while I will see errors in the compare, data appearing
> > at the wrong offset in the file.  The amount of data is small (<64k),
> > always an 8k boundary at a large offset discrepancy (100's of megs).  I've
> > attached the mkoffsetfile.c and cmpoffsets.c programs used for testing.
> >
> > Sample of cmpoffsets output :
> >
> > 431128576-431161343 (32768) (held data from 738426880-738459647)
> >  starts at a 65536-byte block
> >  ends at a 524288-byte block
> >
> > Hope this helps.
> >
> > Andy
> 
>