Re: tsearch2 poor performance

Kris Kiger wrote:
> Josh,
>
>    I am running my tests on a dual processor PIII 1 GHz machine with 2Gb
> of RAM.  There are four hard drives set up.  One for OS/logging and
> three in a raid-5 configuration for the postgres data directory.
>

What about other factors?

effective_cache_size
random_page_cost
sort_mem

FYI that example I gave was on a Dual P4-Xeon with 4 Gigs of ram and a
RAID5 over 6 drives.

Just curious.

J



> Kris
>
> Joshua D. Drake wrote:
>
>> Hello,
>> I might of missed this on a previous message, BUT what type of
>> hardware are we dealing with here? Is it possible that we just don't
>> have enough IO/RAM to push this?
>> J
>> Kris Kiger wrote:
>>
>>> Oleg,
>>>    Thanks for the help on this.
>>>    The query I used to return the 508 number is:
>>>         SELECT * FROM stat('SELECT vector FROM product') ORDER BY
>>> ndoc desc, word ;
>>>      Testing says, the more words I use, the faster the query is.  My
>>> original search word, 'oil', appears in 226,357 documents 233,266
>>> times. As far as distinct words go, 'oil' is middle of the road for
>>> occurences.  As it is set up now, the best search time I am getting
>>> on this single word is roughly 22 seconds. Kris
>>>
>>> Oleg Bartunov wrote:
>>>
>>>> Kris,
>>>>
>>>> do you actually have only 508 disctinct words ? Could you try
>>>> more complex queries, say 2-3 words. Does these queries run faster ?
>>>>     Oleg
>>>> On Mon, 27 Sep 2004, Kris Kiger wrote:
>>>>
>>>>> Regardless of caching, the queries are still taking 19~20 seconds
>>>>> to run
>>>>> on the 3,000,000 rows.  I've played with performance tuning and
>>>>> nothing
>>>>> seems to make much of a difference.  If I am reading that list from
>>>>> stat
>>>>> correctly, then I am operating on  508 distinct words.  Is this the
>>>>> performance I should expect from tsearch2?  Or is something still
>>>>> awry?
>>>>> I'm inclined to think  something else is wrong, after reading some
>>>>> other people's tsearch performance stats.  Thanks!
>>>>>
>>>>> Kris
>>>>
>>>>
>>>>     Regards,
>>>>         Oleg
>>>
>>>
>
>


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