On Tue, May 7, 2013 at 7:52 PM, Amit Langote wrote:
> So, any rise in number of XLogFlush() calls should roughly
> be accounted for by increased throughput. Am I right in interpreting
> it this way?
I think so. There certainly isn't any question that the increased
throughput and the increased num
> Why is that surprising? Most of those XLogFlush() calls will recheck
> the flushed-up-to point, and realize that another backend assumed the
> role of group commit leader, and flushed their WAL for them, so aside
> from the wait, the call to XLogFlush is cheap for that individual
> backend. It's
On Tue, May 7, 2013 at 8:13 AM, Amit Langote wrote:
> Profiling results show that XLogFlush() is called about twice as many
> times after this patch while for XLogWrite() count remains about same
> as before. This patch modifies XLogFlush() such that it offers the
> said performance gain by allev
Hello,
I have been trying to understand how group commit implementation works
the way it does after 9.2 group commit enhancement patch
(9b38d46d9f5517dab67dda1dd0459683fc9cda9f on REL9_2_STABLE). I have
observed some behavior in this regard that I could not understand.
Profiling results show that
