On Mon, Dec 14, 2015 at 12:18 PM, Vladimir Sitnikov < sitnikov.vladi...@gmail.com> wrote: > > a global lock would be good enough for a proof of concept that only > evaluates cache hit ratios. > > I think emulator can be used to check hit ratios. That way we can see > how different algorithms affect hit ratio. > > Is there a set of traces of "buffer load events"? (I did some Google > searches like "postgresql buffer cache trace" with no luck) > Is there an option that enables tracing of each requested buffer Id? >
To get the detailed trace for each buffer, I think you can use dynamic tracing as explained in documentation [1]. Another simple way could be to use: Explain (Analyze, Buffers) <sql_statement> This will give blocks hit and read numbers which could be useful in your experiments. [1] - http://www.postgresql.org/docs/devel/static/dynamic-trace.html With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com