Re: contrib/cache_scan (Re: What's needed for cache-only table scan?) - Mailing list pgsql-hackers

On Thu, Mar 6, 2014 at 10:15 PM, Kohei KaiGai <kaigai@kaigai.gr.jp> wrote:
> 2014-03-06 18:17 GMT+09:00 Haribabu Kommi <kommi.haribabu@gmail.com>:
>> I will update you later regarding the performance test results.
>>

I ran the performance test on the cache scan patch and below are the readings.

Configuration:

Shared_buffers - 512MB
cache_scan.num_blocks - 600
checkpoint_segments - 255

Machine:
OS - centos - 6.4
CPU - 4 core 2.5 GHZ
Memory - 4GB

                                         Head          patched          Diff
Select -  500K                772ms        2659ms        -200%
Insert - 400K                   3429ms     1948ms          43% (I am
not sure how it improved in this case)
delete - 200K                 2066ms     3978ms        -92%
update - 200K                3915ms      5899ms        -50%

This patch shown how the custom scan can be used very well but coming
to patch as It is having
some performance problem which needs to be investigated.

I attached the test script file used for the performance test.

Regards,
Hari Babu
Fujitsu Australia