The user space daemon in afs doesn't do much of anything. It's there
primarily to launch kernel threads and set up the cache. 

-- Nathan

------------------------------------------------------------
Nathan Neulinger                       EMail:  [EMAIL PROTECTED]
University of Missouri - Rolla         Phone: (573) 341-4841
Computing Services                       Fax: (573) 341-4216


> -----Original Message-----
> From: Nathan Ward [mailto:[EMAIL PROTECTED] 
> Sent: Thursday, February 27, 2003 1:52 PM
> To: [EMAIL PROTECTED]
> Cc: Michael Robokoff; openafs
> Subject: Re: [OpenAFS] Performance
> 
> 
> Well I'd expect that it goes slower as your cache size is 
> exceeded as it 
> then needs to start getting that data to the server. Or is 
> the cache for 
> read operations only?
> 
> I notice that there are around about the same number of 
> packets/sec as 
> context switches/sec on my client machines. I wonder if 
> switches between 
> userland and kernel could be to blame... ? Who sends packets 
> in OpenAFS, 
> the userspace daemon or the kernel?
> 
> Nathan
> 
> [EMAIL PROTECTED] wrote:
> 
> > Could the slowness you see with your dd write test be 
> related to the  
> > cache exhaustion issue that I raised recently, when writing a file  
> > larger than your cache size.  Your test writes a 1 GB file, so if 
> > your  cache is smaller than this, you will see poor 
> performance once 
> > your  cache size is exceeded.
> > 
> --------------------------------------------------------------
> ---------- 
> > -- 
> > Edward Moy
> > Apple Computer, Inc.
> > [EMAIL PROTECTED]
> >
> > (This message is from me as a reader of this list, and not 
> a statement
> > from Apple.)
> >
> > On Thursday, February 27, 2003, at 11:15  AM, Nathan Ward wrote:
> >
> >> I see pretty bad performance to tell you the truth.
> >> I can read and write ~60mb/s directly to my raid array, but when 
> >> using  OpenAFS (locally or remotely) to the same array, I 
> get around  
> >> 6-10MB/s, I have seen up to 25MB/s over a peice of 
> 1000Mbps fibre.  
> >> Client and Server are both dual P3-1ghz with 1024mb ram. I notice 
> >> the  context switches on the server at this time jump to ~10000/s, 
> >> and on  the client ~40000/s. I imagine this is the source of my 
> >> slowdown, but  I havn't had a chance to look into it.
> >>
> >> I'd be interested if anyone else has the same level of context  
> >> switches going on.
> >>
> >> This is while doing a large sequential write operation (dd  
> >> if=/dev/zero of=/afs/alb-nz.esphion.com/public/dd.out bs=256k  
> >> count=4096).
> >>
> >> Michael Robokoff wrote:
> >>
> >>> Does anyone have any Open AFS performance information they can 
> >>> share  with me. I plan on doing a couple benchmarks and I 
> would like 
> >>> to have  some idea of what to expect.
> >>
> >
> > _______________________________________________
> > OpenAFS-info mailing list
> > [EMAIL PROTECTED]
> > https://lists.openafs.org/mailman/listinfo/openafs-info
> >
> >
> 
> 
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