On 17 November 2014 05:49, Rajeev rastogi <rajeev.rast...@huawei.com> wrote:
>> * Single column bigint index > It gives around 5% improvement. I confirm 5% improvement in both short and long index scans, on the least beneficial datatype. Looks likely to be a very positive win overall. TEST 1: 100000x select id2 into x from tbl2 where id2>990000 limit 1; Patched Time: 617.026 ms Time: 604.769 ms Time: 613.392 ms Time: 600.484 ms Time: 607.895 ms Time: 609.366 ms Time: 606.187 ms Time: 602.643 ms Time: 613.115 ms Time: 605.705 ms Unpatched Time: 642.786 ms Time: 649.880 ms Time: 637.400 ms Time: 635.937 ms Time: 641.210 ms Time: 641.988 ms Time: 637.839 ms Time: 640.265 ms Time: 640.237 ms Time: 637.669 ms TEST 2 10000x select count(*) into x from tbl2 where id2>990000; Patched: Time: 17277.083 ms Time: 17373.752 ms Time: 17208.220 ms Unpatched: Time: 18186.062 ms Time: 18067.664 ms Time: 18118.807 ms >> The explanatory comments need some work to more clearly explain what >> this patch does. > > Please help me to understand this point, you want me to add more comments > about patch in this mail chain or in code. The language used in the comments is not clear enough. I'll do my best to improve that, then look to commit this in about 5 hours. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
