(Illustration by Gaich Muramatsu)
>>>>> "Lionix" == Lionix <lio_at_absium.com> writes: >> We plan to use coda on the whole faculty to provide user home >> dirs and data. This would be nearly 200 machines and 1000 >> users. Is coda ready for such a usage or would we run in >> trouble? Lionix> Wow ! I've seen a 30 machines configuration stuff in the Lionix> ml two years ago but i've never heard about so big Lionix> deployement of coda-fs. Guess you'll have to define Lionix> multiple realms. I don't see why. Maybe multiple servers, multiple VSGs for performance or organizational reasons, but Coda scales well in that direction. >> Is it possible to deactivate the cache on the client machines >> at runtime? Lionix> I would say no.. caching mecanism is a full part of the Lionix> coda client ( venus ). "No" is right. The way the client works is to fetch whole files into the cache (thus performance of open() on very large files is poor), and access them from there. RVM (where the directory structure is kept) can be disabled when initializing the client, but this means you need to keep all information in memory, and of course it's not persistent. Increases startup costs and risk of mutation loss if there's a crash before saving. >> Does coda need a process in userspace to access the coda fs? Lionix> If you mean a process started by the user the reponse is Lionix> no. Coda must be started by the root, init script stuff. Ie, "yes". The coda client is quite complex; the kernel provides only enough services to implement to VFS interface, so that ordinary programs can use usual file APIs. All real work is done by upcalls into the client (which is actually a server from the point of view of other processes accessing it: network Unix process <-+ +--> venus daemon <---------> coda server | | A VFS | | Coda | downcall | | upcall | | | | V V V kernel file cache and any file data returned follows the opposite path. -- Institute of Policy and Planning Sciences http://turnbull.sk.tsukuba.ac.jp University of Tsukuba Tennodai 1-1-1 Tsukuba 305-8573 JAPAN Ask not how you can "do" free software business; ask what your business can "do for" free software.Received on 2003-11-30 21:16:21