Coda File System

Re: maximum cache size in venus

From: Casey Helfrich <>
Date: Tue, 11 May 2004 09:19:19 -0400 (EDT)
Just FYI, I'm not sure it this little data point will help much in the
current situation, but we regularly run 8GB venus caches in the lab at
Intel Research without issue.  In general we are using RedHat Linux,
2.4.22.etc... kernel, and we always compile everything from source on the
machine it is meant for.

We are using Coda in a highly demanding way and are using the Venus cache
to guarantee the local presence of a large ammount of data even when

Granted, we know alot about the structure of the data we are sharing
(less than 128KB of data payload per file, always 512 files per
directory), but I have not been able to repeat your situation below.

Casey Helfrich
Intel Research Pittsburgh

On Mon, 10 May 2004, Steve Simitzis wrote:

> On 05/10/04, Jan Harkes <> wrote:
> > I don't know. My cache is typically in the order of 200-250MB.
> well, i'll continue my experiments then, to see how high i can raise
> the cache without problems. i finally hit a crash at 1.9GB, unfortunately,
> so my theory about a 2GB upper bound is now dead in the water. :)
> another consideration is, how high should a cache be for a given
> quantity of data? should i reasonably expect that i should be able to
> cache the entire filesystem, so venus can maintain somewhat of a local
> disk copy of everything, or should i think of it more as a true cache
> of the data?
> i currently have 19GB of data, so a 250MB cache probably isn't too
> shabby. though, a larger cache has saved me in situations when
> codasrv dies or becomes unreachable.
> tradeoffs, tradeoffs.
> > 266 is precisely 256 + 10, which would match a wraparound on the link
> > count field. But... we don't have cross-directory hardlinks, and I find
> > it hard to believe that you would have so many links to one object in a
> > single directory.
> i also find it hard to believe. our entire dataset is content uploaded
> via web forms, with little or no direct human interaction. there are
> no extra links, hard or soft.
> --
> steve simitzis : /sim' - i - jees/
>           pala : saturn5 productions
> : 415.282.9979
>   hath the daemon spawn no fire?
Received on 2004-05-11 09:28:48