[OpenAFS-win32-devel] Experiences with new AFS releases

[ota@surfvi.com]

> I ran some tests to confirm these performance numbers on v1.5.10.  The
> command "ls -F | wc" took 76.1 seconds (user+sys = 0.37) to list 243
> files: 0.31sec/file.
>
> Then I reinstalled v1.4.1 (from Apr 2006) and ran the same tests.  The
> same "ls -F | wc" command took 0.485s (user+sys = 0.29) to list the 243
> files: 0.002 sec/file.

It occurred to me that I was not very clear about these timing numbers. 
  In both
these cases I was measuring *warm* cache times.  I had already listed the
directory once, which was quite a bit slower since it had to actually fetch
stat information (and I suspect at least some of the data as well, maybe the
first chunk?).  But then I ran the ls -F again and collected the times.  For
1.4.1, it is clearly not contacting the file server when serving warm cache
stat results.  However, for 1.5.10, the time indicates that the cache manager
is making at least one RPC to the file server for each file in the directory,
even if the file is already in the cache.

Sorry for any confusion,
Ted Anderson

Quoting Ted Anderson <ota@surfvi.com>:
> I wanted to report on my experiences running the new OpenAFS releases.
> I installed 1.5.10 a few days ago because it was the recommended release
> for Windows users (I am running W2K+SP4).  While it seemed to work okay,
> I noticed that it was very slow on some things.  Some causal
> measurements suggested that stat'ing each file was taking about 1/3 of a
> second.  So "ls -l" in a directory containing 200 files was taking about
> a minute.  The previous version of AFS (1.4.1) was not nearly so slow.
>
> I am running AFS on a T43 laptop from home, connected to the internet
> via a medium speed wireless connection (about 256kbps) and to work over
> a VPN.  The ping  times to the file servers in my home cell (behind the
> VPN) are pretty large: about 150ms during the tests I conducted.
>
> I ran some tests to confirm these performance numbers on v1.5.10.  The
> command "ls -F | wc" took 76.1 seconds (user+sys = 0.37) to list 243
> files: 0.31sec/file.
>
> Then I reinstalled v1.4.1 (from Apr 2006) and ran the same tests.  The
> same "ls -F | wc" command took 0.485s (user+sys = 0.29) to list the 243
> files: 0.002 sec/file.
>
> Next I figured I should try the latest stable release: 1.4.2a.  However,
> I was not able to get it to work at all with my home cell.  I did have
> some results with a different AFS cell on the same VPN and was also able
> to access /afs/openafs.org.  I don't know what is different about my
> home cell, but all attempts to access it lead to hangs and I could not
> stop the OpenAFS Client Service.  It required an uninstall and an extra
> reboot to clean it off my system.  The event log contained many AFS
> messages during startup, several of which mentioned KfW.  I do not have
> this package installed, so perhaps the logic to handle the case where it
> is unavailable is not working.
>
> After a few hours of rebooting, installing and uninstalling, I was able
> to get the old AFS reinstalled and the performance is back to what I am
> used to.
>
> I can provide excerpts from EventLog, output from the tests I ran or
> other details about my system or environment.  Let me know what would be
> helpful.
>
> Ted Anderson