03.03.2016 15:07, Vlad Khorsun wrote: >> I wouldn't expect much from lock manager, but hash joins can get >> significant boost, >> >especially on long keys. > You don't need "server with dozen of cores" to check it, isn't is ?
You are right, this part I can test even with my notebook. But will you believe my numbers?.. Here they are: > SQL> show version; > ISQL Version: WI-V3.0.0.32342 Firebird 3.0 Release Candidate 2 > Server version: > Firebird/Windows/Intel/i386 (access method), version "WI-V3.0.0.32342 > Firebird 3.0 Release Candidate 2" > on disk structure version 12.0 > SQL> select count(*) from t1 join t2 on t1.a=t2.a; > > PLAN HASH (T2 NATURAL, T1 NATURAL) > > COUNT > ===================== > 32 > > Current memory = 342822008 > Delta memory = 0 > Max memory = 342998536 > Elapsed time= 1.775 sec > Buffers = 40000 > Reads = 0 > Writes = 0 > Fetches = 218290 > > SQL> show version; > ISQL Version: WI-T4.0.0.32373 Firebird 4.0 Unstable > Server version: > Firebird/Windows/AMD/Intel/x64 (access method), version "WI-T4.0.0.32373 > Firebird 4.0 Unstable" > on disk structure version 12.0 > SQL> select count(*) from t1 join t2 on t1.a=t2.a; > > PLAN HASH (T2 NATURAL, T1 NATURAL) > > COUNT > ===================== > 32 > > Current memory = 354135072 > Delta memory = 0 > Max memory = 354316480 > Elapsed time= 0.924 sec > Buffers = 40000 > Reads = 0 > Writes = 0 > Fetches = 218290 -- WBR, SD. ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
