Re: Regex performance issue

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Alexandru Coseru" <alexandru(dot)coseru(at)totaltelecom(dot)ro>
Cc: "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Regex performance issue
Date: 2006-12-03 04:05:12
Message-ID: 12526.1165118712@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

"Alexandru Coseru" <alexandru(dot)coseru(at)totaltelecom(dot)ro> writes:
> Anyway , anybody has a clue why this regex is that CPU intensive ?

The EXPLAIN result you posted offers *no* evidence that the regexp is
CPU intensive. All you know is that it took 850+ msec to fetch 5200
rows from disk and apply the regexp filter to them. There's no evidence
here that that was CPU time and not I/O time.

regards, tom lane

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Oleg Bartunov 2006-12-03 07:05:17 Re: Regex performance issue
Previous Message Scott Marlowe 2006-12-03 01:31:37 Re: Regex performance issue