[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: How to overcome the NFS limitation

From: Nuutti Kotivuori <naked_at_iki.fi>
Date: 2004-03-23 14:47:52 CET

Lukas Ruf wrote:
> is there any way to overcome the NFS problem for a repository?

Well, it is time to read with a fine comb what is actually being said:

  http://www.sleepycat.com/docs/ref/env/remote.html

First of all - even if you do this, there must be only one machine
accessing the repository at a time - this shouldn't be a problem for
you if you run a separate server and just want the storage to be on an
NFS mounted filesystem.

What needs to be supported:

  - Locking: Linux mounting Solaris with NFSv3 should handle this.

  - Fsync: If the filesystem is not async mounted, fsync call should
    bring the data to disk even over NFSv3, so it should be okay.

  - Memory mapping: Should work in general. Not 100% sure if different
    processes see the same memory space - if not, then that is a
    problem.

  - Mutexes: No idea really. I am not even sure what kind of mutexing
    does Berkeley DB use.

So, if you manage to somehow assure that all of these points are
fulfilled, you should be able to have your repository over NFS.

But - this is just trying to be helpful - if *anything* goes wrong,
your data is hosed and you have to go for backups. In the worst case,
you might not even notice it at first, only later on.

If you are willing to experiment, you could try to run the Berkeley DB
testsuite over NFSv3 first - I'm not sure if it manages to tickle all
the access cases, but atleast some it does.

-- Naked

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@subversion.tigris.org
For additional commands, e-mail: users-help@subversion.tigris.org
Received on Tue Mar 23 14:48:36 2004

This is an archived mail posted to the Subversion Users mailing list.