Coda File System

Re: Coda lossage

From: Troy Benjegerdes <>
Date: Tue, 3 Aug 2004 20:34:57 -0500
On Fri, Jul 30, 2004 at 12:52:00PM -0400, Jan Harkes wrote:
> On Sun, Jul 25, 2004 at 02:14:54PM -0400, wrote:
> >    From: Ivan Popov <>
> > 
> >    (yet I do not seem to find how big your client caches were)
> > 
> > Pretty big, varying from 100Mb to 10Gb.
> I use a 200MB cache which works pretty well. It translates to about 8000
> locally cached objects.
> But without tweaks, a 10GB Coda client will try to cache up to 420000
> files. This in itself shouldn't be a problem except for the fact that
> there are a couple of places where every object is compared to every
> other object. So with 8K objects there are about 64 million
> comparisons, while with 420K objects there are more than 176 billion.

I think it would do everyone a lot of good to separate the cache size
limit from the number of files limit. I'd like to have 8000 files, but
20GB of cache. (for MP3 files, for instance). How do I do this?

> We've been working on fixing such implementation problems within the
> existing framework which can be quite difficult at times. Intermezzo was
> a 'start from scratch' attempt, but I don't think it really took off.

As someone who started with coda, gave up, went to intermezzo, and gave
up on that, and is now back at Coda, I'd say intermezzo definitely
didn't take off. It appeared to have a cleaner, more modular design, but
it completely lacked any userland tools or documentation on how to
resolve a conflict. The intermezzo kernel module also had some
implementation issues that a bunch of the kernel developers didn't like,
and it has since been dropped from Linux.

Coda has kernel modules for a bunch of different OS'es, and the only
complaint about the module I've heard from linux developers is that it
seems unmaintained, but that's only because it doesn't need to change
very much.
Received on 2004-08-03 21:42:25