On Thu, Apr 11, 2013 at 10:09 AM, Amit Kapila <amit.kapila@huawei.com> wrote:
> Consider the case old-master crashed during flushing the data page, now you
> would need full page image from new-master.
> It might so happen that in new-master Checkpoint would have purged (reused)
> the log file's from that time line, in that case
> it will be difficult to get the full page image, user can refer WAL archive
> for that, but I think it will not be straight forward.
Using a WAL archive is standard procedure when you do not wish to take
new base backups all the time. This already works now, when archive
recovery is set up the WAL will be automatically fetched from the
archive.
> One more point, what will be the new behavior when there are 2 transactions
> one has synchronous_commit =off and other with on?
Exactly the same as now - waiting for commit record replication when
reporting commit success to the client and waiting for WAL replication
before writing a data page are orthogonal features.
Regards,
Ants Aasma
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