On Wed, Sep 14, 2016 at 10:25 AM, Dilip Kumar <dilipbal...@gmail.com> wrote: > I have tested performance with approach 1 and approach 2. > > 1. Transaction (script.sql): I have used below transaction to run my > bench mark, We can argue that this may not be an ideal workload, but I > tested this to put more load on ClogControlLock during commit > transaction. > > ----------- > \set aid random (1,30000000) > \set tid random (1,3000) > > BEGIN; > SELECT abalance FROM pgbench_accounts WHERE aid = :aid for UPDATE; > SAVEPOINT s1; > SELECT tbalance FROM pgbench_tellers WHERE tid = :tid for UPDATE; > SAVEPOINT s2; > SELECT abalance FROM pgbench_accounts WHERE aid = :aid for UPDATE; > END; > ----------- > > 2. Results > ./pgbench -c $threads -j $threads -T 10 -M prepared postgres -f script.sql > scale factor: 300 > Clients head(tps) grouplock(tps) granular(tps) > ------- --------- ---------- ------- > 128 29367 39326 37421 > 180 29777 37810 36469 > 256 28523 37418 35882 > > > grouplock --> 1) Group mode to reduce CLOGControlLock contention > granular --> 2) Use granular locking model > > I will test with 3rd approach also, whenever I get time. > > 3. Summary: > 1. I can see on head we are gaining almost ~30 % performance at higher > client count (128 and beyond). > 2. group lock is ~5% better compared to granular lock.
Forgot to mention that, this test is on unlogged tables. -- Regards, Dilip Kumar EnterpriseDB: http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
