Re: Is the warning in http://subversion.tigris.org/faq.html#bdb-recovery still relevant?

Eric Hanchrow <offby1@blarg.net> writes:

> Today on #svn sussman suggested that, since "svnadmin recover" gets an
> exclusive lock on the repository before starting work, it is quite
> safe to run at any time. That suggests to me that the above-mentioned
> warning is no longer needed. Is this really the case? And if so, is
> the following paragraph ("Make absolutely sure you disable all access
> to the repository before doing this ...") itself still relevant?

I believe it's safe to run "svnadmin recover" on a live repository
provided all other access also goes through libsvn_repos. If there is
a lot of repository activity you may need to try repeatedly, or use
the --wait option, to get the exclusive lock. Using the BDB tools
while running "svnadmin recover" or running db_recover while allowing
normal libsvn_repos access is likely to cause problems. I guess we
could make the warning db_recover specific.

On a related note, I think the repository lock suffers from the
"per-process" problem that affected the libsvn_fs_fs lock, the lock
doesn't provide exclusive access within a multi-threaded process on
Unix. That's not a problem the way we currently use it, since
svnadmin is single-threaded, but a multi-threaded program might have
problems. I suppose we should either add a mutex or document the
restriction.

-- 
Philip Martin
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@subversion.tigris.org
For additional commands, e-mail: dev-help@subversion.tigris.org