Re: [GENERAL] So slow inserts... Why?

I removed your first mail, but if i remembered it right you was using PHP.
I have seen on my server (dual P5/100) that the "startup" cost of the
backend is rather high.
If you is using PHP and not using persistent connection (or whatever it was
called) you may have a lot of
start/stop of backends.

Whatewer the reason is, 1 transaction/sec is awfully slow. Something must
be wrong.
What other things is running on this machine. Is it highly loaded?

/Johan




Michal Samek <webmaster@tony.cz> on 99-05-26 16:15:10

To:   Johan Granlund/Solid AB
cc:   pgsql-general@postgresql.org
Subject:  Re: [GENERAL] So slow inserts... Why?




johan.granlund@solid.se wrote:
>
> As i dont know anything about triggers:)
> Have you done a vacuum on the databases to clear out old transactions?

I recreated the table, so I think there is not necessary to vacuum it
(it takes unbelieveable amount of time); maybe when I'm filling the
table by sending a lot of INSERT queries I should sometimes between
inserts do a vacuum ? It looks strange for me.

And many thanks for your help; I was thinking about dropping indexes and
trigger, but It's impossible. Imagine this is not just a series of
insert queries, the process I'm using is (simplicied): For each dbase
record (the catalogue from the music label) to look-up if exist and if
so, update; if no, insert. So I can't drop indexes which are needed by
look-up function; nor can't drop trigger because it tracks inserts /
updates of my table.
I'm testing to group inserts / updates to blocks enclosed with
transaction BEGIN; END;, but it now looks that it will help only little.

PS I plan to rewrite the whole thing to Mysql (even it's no triggers, it
will be harder but possible of course) and to report the result here if
will be interesting)


--
Michal Samek, Tony distribuce s.r.o.
webmaster@tony.cz  (++420659/321350)
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