From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
---|---|
To: | Gregory Stark <stark(at)enterprisedb(dot)com> |
Cc: | pgsql-patches(at)postgresql(dot)org, "Jan Wieck" <JanWieck(at)Yahoo(dot)com> |
Subject: | Re: Proposed patch to change TOAST compression strategy |
Date: | 2008-03-07 23:23:12 |
Message-ID: | 8565.1204932192@sss.pgh.pa.us |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-patches |
Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
>> * Adds an early-failure path to the compressor as suggested by Jan:
>> if it's been unable to find even one compressible substring in the
>> first 1KB (parameterizable), assume we're looking at incompressible
>> input and give up. (There are various ways this could be done, but
>> this way seems to add the least overhead to the compressor's inner
>> loop.)
> I'm not sure how to test the rest of it, but this bit seems testable. I fear
> this may be too conservative. Even nigh incompressible data will find a few
> backreferences.
> I'll try some tests and see.
On the strength of Teodor's favorable test, I went ahead and applied
this patch as-is. We can certainly tweak the compressor logic again
if you can show an improvement by changing it further.
regards, tom lane
From | Date | Subject | |
---|---|---|---|
Next Message | Andrew Dunstan | 2008-03-08 00:16:11 | Re: CopyReadAttributesCSV optimization |
Previous Message | Tom Lane | 2008-03-07 21:20:01 | Re: Re: [PATCHES] a tsearch2 (8.2.4) dictionary that only filters out stopwords |