Re: GIN improvements part2: fast scan

From: Alexander Korotkov <aekorotkov(at)gmail(dot)com>
To: Heikki Linnakangas <hlinnakangas(at)vmware(dot)com>
Cc: Tomas Vondra <tv(at)fuzzy(dot)cz>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: GIN improvements part2: fast scan
Date: 2014-02-09 10:11:50
Message-ID: CAPpHfdsMac=yQkkMi+HPN96EiCjvE1wBt9tveENq0tjti3r88w@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Fri, Feb 7, 2014 at 5:33 PM, Heikki Linnakangas
<hlinnakangas(at)vmware(dot)com>wrote:

> On 02/06/2014 01:22 PM, Alexander Korotkov wrote:
>
>> Difference is very small. For me, it looks ready for commit.
>>
>
> Great, committed!
>
> Now, to review the catalog changes...

I've rebased catalog changes with last master. Patch is attached. I've
rerun my test suite with both last master ('committed') and attached
patch ('ternary-consistent').

method | sum
------------------------+------------------
committed | 143491.715000001
fast-scan-11 | 126916.111999999
fast-scan-light | 137321.211
fast-scan-light-heikki | 138168.028000001
master | 446976.288
ternary-consistent | 125923.514

I explain regression in last master by change of MAX_MAYBE_ENTRIES from 8
to 4. However I'm not sure why ternary-consistent show so good results.
Probably it's because some optimizations you did in committed version which
wasn't visible because of change of MAX_MAYBE_ENTRIES.
I'm not sure about decision to reserve separate procedure number for
ternary consistent. Probably, it would be better to add ginConfig method.
It would be useful for post 9.4 improvements.

------
With best regards,
Alexander Korotkov.

Attachment Content-Type Size
gin-ternary-consistent.patch application/octet-stream 30.4 KB

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Alexander Korotkov 2014-02-09 10:17:12 Re: Small GIN optimizations (after 9.4)
Previous Message Marco Atzeri 2014-02-09 06:12:12 Re: narwhal and PGDLLIMPORT