[TYPO3-dev] indexed_search kills server
Ernesto Baschny [cron IT]
ernst at cron-it.de
Wed May 21 12:05:09 CEST 2008
Steffen Kamper wrote: on 21.05.2008 11:26:
> on my server i encountered massive problems with indexed_search.
>
> Have a look to query times:
>
> # Time: 080521 10:18:31
> # User at Host: web2[web2] @ localhost []
> # Query_time: 555 Lock_time: 0 Rows_sent: 30 Rows_examined: 21263272
> SELECT IR.phash
> FROM index_words IW,
> index_rel IR,
> index_section ISEC
> WHERE
> IW.baseword LIKE '%einrichtung%'
> AND IW.wid=IR.wid
> AND ISEC.phash = IR.phash
> AND ISEC.rl0 IN (1)
> AND is_stopword=0
> GROUP BY IR.phash;
Even for this amount of rows it seems mysql is taking a bit "too much"
time. I guess that your server is not well tuned for the Apache + MySQL
configuration.
In one particular installation I have about 6 million entries in the
index_rel table (where you have 21 million) and the same query returns
in about 0.21 secs, and this is being hosted on a virtual environment
(xen based).
So I guess your 555 secs are caused by memory exhaustion, server having
to swap and the whole I/O performance going down to the ground. Consider
tuning the mysql + apache combination to not go much over the amount of
available RAM (by limiting max_connections and MaxClients) and tweak
MySQL to make better use of the RAM. Also make sure you have fast
HDD-access, make use of NCQ (if possible), etc.
Cheers,
Ernesto
More information about the TYPO3-dev
mailing list