Coda File System

Re: reliability,performance ?

From: Michel Brabants <michel.brabants_at_euphonynet.be>
Date: Sun, 3 Sep 2006 20:39:23 +0200
Hello,

I think I got it at least partly wrong, the issue was client-server related.

Thank you and greetings,

Michel

Op zondag 3 september 2006 20:35, schreef Michel Brabants:
> Hello,
> 
> so if I got ir right;
>  * Coda is normally reliable ... although this is still a littl ebit 
> troubling. Ok, I plan to have replication, what should help.
>  * I can't have files bigger than 2 GB because of how coda is implemented. It 
> doesn't have anything to do with the client-side cache. ( Or does it allow 
> for files as big as the cache? Although it still is a not-so-nice limit, the 
> cache I would create would/could be multiple gigabytes.
> 
> If I deploy coda, I will be using jfs for the client-side caches normally. Has 
> it any advantages if I use a journalling file-system for the servers? Does 
> coda do journalling?
> 
> Thank you for your time and answer. Greetings,
> 
> Michel
> 
> Op woensdag 30 augustus 2006 10:06, schreef michel.brabants_at_euphonynet.be:
> > Hello,
> > 
> > for what it is worth, my thoughts about coda. I really want to deploy coda
> > (it seems a good distributed filesystem), but the following things are
> > stopping me from doing this:
> > 
> >  * 2 GB file-limit on linux. I've read that there is a patch for windows,
> > but the question is how long before a stable patch wil be merged with the
> > linux-code?
> >  * The faulty re-integration you mentionned that happens from time to time
> > it seems. This is a bad one or can it be detected and solved manually (at
> > least it is detected and solvable then). I read about a coda-rewrite, is
> > this already done in coda 6.x?
> > 
> > We need the distributed filesystenm to eventually (can be within a month
> > or later) store terabytes of data. I don't think that this is a problem
> > with coda.
> > I think that coda is my filesystem of choice for the moment, if it wasn't
> > for the above things.
> > I want to add one last thing. I read that if a client is in disconnected
> > mode, 2x the space of files is/can be used because of keeping a copy of
> > the latest connected-version or so? Maybe I didn't get it and maybe you do
> > it already, but couldn't you for example only specify the blocks (on the
> > filesystem) that have changed? Maybe there are better solutions.
> > ASR seems to be nice. Reintegration of subversion-repositories could maybe
> > be done by using subversion-merge or so in my case.
> > 
> > Greetings,
> > 
> > Michel
> > 
> > > On Sat, Aug 26, 2006 at 01:06:50AM -0400, Jan Harkes wrote:
> > >> operations. We also take a hit on the network transfers, last time I
> > >> measured I saw writes in the order of 3MB/s to a single replica, 6MB/s
> > >> to a doubly replicated volume, and 7.5 or so to a triply replicated
> > >> volume. Not 100% sure anymore and this was a couple of years ago on a
> > >> 100Base-T network before we added things like encryption.
> > >
> > > btw. I am not terribly concerned about not being able to saturate a
> > > gigabit network. In my mental model the local cache is large enough to
> > > cache everything I care about, the period prefetching (hoarding) will
> > > pull in anything that may have changed on the servers and the
> > > write-disconnected operation will send any local changes back to the
> > > servers in the background.
> > >
> > > Jan
> > >
> > >
> > 
> > 
> > 
> 

Received on 2006-09-03 14:40:34