[bzr-svn] There is should be some lock problems around sqllite.

[Jelmer Vernooij]

(CC'ing the bug. Usually, the bug tracker is the right place for
comments specific to a particular bug. )

On Wed, 2011-08-03 at 00:43 +0800, 罗勇刚(Yonggang Luo) wrote:
> Maybe this is the solution.

> http://stackoverflow.com/questions/5529820/sqlite3-operationalerror-database-is-locked

> We need specify separate sql database for each repo, not for each url.
That would negate a lot of the benefit of actually having a cache. It's
possible to have multiple processes working against the same bzr
repository - which would mean we could still hit locking issues.

We don't need a database that can support multiple writers with high
concurrency. It's fine if we have to wait for another process to release
the database lock - the only thing that it could be working on is
updating the cache, and that's what the process that's waiting would do
too.

The main thing that's missing is actually asking sqlite to wait for the
lock to be released rather than raising an exception immediately if it
finds a lock. IIUC this is possible, but I haven't had the time to look
up the right functions in the API, write some tests and patch bzr-svn to
use it.

Cheers,

Jelmer

> 
> 2011/8/2 Jelmer Vernooij <jvernooij at gmail.com>
>         On Tue, 2011-08-02 at 20:44 +0800, 罗勇刚(Yonggang Luo) wrote:
>         > Delete br llvm/branches/release_21:41946
>         > Delete br llvm/branches/release_21:41945
>         > Delete br llvm/branches/release_21:41943
>         > Delete br llvm/branches/release_21:41920
>         > bzr: ERROR: sqlite3.OperationalError: database is locked
>         
>         Please see the bug tracker:
>         
>         This is http://pad.lv/685251
>         
>         Patches welcome.
>         
>         Cheers,
>         
>         Jelmer
>         
>         
> 
> 
> 
> -- 
>          此致
> 礼
> 罗勇刚
> Yours
>     sincerely,
> Yonggang Luo
> 
>