[OpenAFS] Salvager did not run automatically on solaris 9, 1.4.1-rc10

Dale Ghent daleg@umbc.edu
Wed, 19 Apr 2006 01:52:20 -0400

Rainer Toebbicke wrote:
> A little bit off-topic:
> Admittedly I frowned myself for years at voices promoting the use of 
> the namei fileserver in favour of the inode one, until...
> on the inode fileserver the inc(), dec() operations always translate 
> into real I/Os. You cannot do a lot such operations per second, at 
> least I did not find out how.
> This means that cloning (and therefore moving, backing up, ...) 
> volumes is intrinsically slow. With the namei fileserver the speedup 
> is tremendous once you group the intervening fsyncs(). This is 
> relevant for operating a service where people think in volumes of 
> several hundred thousand files. I am still frowning at the otherwise 
> unproductive overhead the namei fileserver induces at every operation.
> Hence only our 1.2.X Solaris servers are still running the inode 
> fileserver, the 1.4.X were switched to namei with up to now (touch 
> wood) no ill effects.
> Now, strictly speaking this is an argument in favour of the link count 
> file that the namei fileserver uses instead of using the inode 
> reference counts. I could well imagine the same technique in the inode 
> fileserver.

We've been running namei on Solaris (a mix of 8, 9, and 10) here at UMBC 
for more than a year, with all AFS servers recently moved to namei on 
Solaris 10 (x86) with seemingly no ill effects directly associated with 
namei.Great performance (well, these /are/ dual Opteron servers), we can 
use UFS logging, and best of all, I got it working on Solaris Nevada 
with ZFS (well, I created and served a volume on that server with no 
problems at least.... just had to force-attach fileserver to the 
ZFS-based /vicepblah mounts.. a proof of concept but warrants further 

You guys (this is directed at the core AFS developers) don't expect 
Solaris's UFS with AFS/inode to be the end-all for ever and ever, do 
you? With production ZFS coming online in a Solaris 10 update as early 
as June (s10u2), and with the features it has, you betcha more people 
will be looking at using AFS/namei and stop using the direct-fs-munging 
dinosaur that is AFS/inode. Perhaps this means that the storage 
subsystem of AFS needs some TLC?