maria-developers team mailing list archive

[Sergei Golubchik <sergii@xxxxxxxxx>]

Hi, MARK!

On Dec 29, MARK CALLAGHAN wrote:
> On Tue, Dec 29, 2009 at 11:23 AM, Sergei Golubchik <sergii@xxxxxxxxx> wrote:
> 
> Is this a potential problem?
> * order of transactions in binlog don't commit record order for InnoDB
> in transaction log
> * binlog rotation occurs
> * last binlog has XIDs 1, 3, 5
> * current binlog has XIDs 2, 4
> * server crashes
> * XID 5 is in state PREPARED (not committed) before the crash

No, it's not a problem.

Because on recovery MySQL only reads the *last* binlog, it needs to
ensure somehow that last binlog has all the information that recovery
needs. Currently a simple solution is used - binlog rotation waits for
all prepared transaction to commit. That is, you can be sure that last
binlog has only XIDs for committed transactions.

> I thought someone explained to me the constraints on binlog rotation
> that might be related to this, but I don't remember the details.

That could've been me :)
 
Regards / Mit vielen Grüßen,
Sergei

-- 
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /   Sergei Golubchik <serg@xxxxxxx>
 / /|_/ / // /\ \/ /_/ / /__  Principal Software Engineer/Server Architect
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