Re: atrocious update performance - Mailing list pgsql-performance

From Aaron Werman
Subject Re: atrocious update performance
Date
Msg-id Law10-OE28zi95HfqR7000142f8@hotmail.com
Whole thread Raw
In response to Re: atrocious update performance  ("Rosser Schwarz" <rschwarz@totalcardinc.com>)
List pgsql-performance
Quick observations:

1. We have an explanation for what's going on, based on the message being
exactly 666 lines long :-)
2. I'm clueless on the output, but perhaps Tom can see something. A quick
glance shows that the strace seemed to run 27 seconds, during which it did:
  count| call
  -------|---------
      84 | _llseek
      40 | brk
      54 | close
      88 | open
      63 | read
in other words, nothing much (though it did *a lot* of opens and closes of
db files to do nothing ).

Can you do another strace for a few minutes against the actual update query
adding the -c/-t options and control-c out?

----- Original Message -----
From: "Rosser Schwarz" <rschwarz@totalcardinc.com>
To: "'Tom Lane'" <tgl@sss.pgh.pa.us>
Cc: <pgsql-performance@postgresql.org>
Sent: Tuesday, March 16, 2004 7:20 PM
Subject: Re: [PERFORM] atrocious update performance


while you weren't looking, Tom Lane wrote:

[trace]

`strace -p 21882` run behind the below query and plan ... below that.

# explain update account.cust set prodid = tempprod.prodid, subprodid =
tempprod.subprodid where origid = tempprod.debtid;

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