With pg_test_timing I can see, that overhead is 48 nsec on my server and 32 nsec on the laptop. what makes this difference and have it any influence on the overall performance?
Tigran. ----- Original Message ----- > From: "Mark Kirkwood" <mark.kirkw...@catalyst.net.nz> > To: "Tigran Mkrtchyan" <tigran.mkrtch...@desy.de>, "Merlin Moncure" > <mmonc...@gmail.com> > Cc: "postgres performance list" <pgsql-performance@postgresql.org> > Sent: Wednesday, September 24, 2014 12:04:12 PM > Subject: Re: [PERFORM] postgres 9.3 vs. 9.4 > > On 24/09/14 21:23, Mkrtchyan, Tigran wrote: > > Hi Merlin et al. > > > > after building postgres 9.4 myself from sources I get the same performance > > as > > with 9.3. The difference was in the value of debug_assertions setting. > > > > Now the next step. Why my 3 years old laptop gets x1.8 times more tps than > > my one month old server? > > And Mark Kirkwood's desktop gets x2 times more tps as well? Is there some > > special optimization > > for i7 which does not work with Intel(R) Xeon(R) CPU E5-2660? > > > > > > Yes - firstly, nicely done re finding the assertions (my 9.4 beta2 was > built from src - never thought to mention sorry)! > > I'd guess that you are seeing some bios setting re the p320 SSD - it > *should* be seriously fast...but does not seem to be. You could try > running some pure IO benchmarks to confirm this (e.g fio). Also see if > the manual for however it is attached to the system allows for some > optimized-for-ssd settings that tend to work better (altho these usually > imply the drive is plugged into an adapter card of some kind - mind you > your p320 *does* used a custom connector that does 2.5" SATA to PCIe > style interconnect so I'd look to debug that first). > > Cheers > > Mark > > -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance