Oracle-L: Re: Autoextend WAIT statistic?

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 27 Nov 2002 12:04:48 -0800
Message-ID: <F001.0050E193.20021127120448@fatcity.com>

Dan,

Your sample from v$session_wait is showing the state as "WAITED SHORT TIME", this
means the 132 'seconds in wait' is actually - 132 seconds since the "open file" wait ended and (in theory) the CPU has been thrashing away ever since.

seconds in wait is only measuring wait time (to a 3 second granularity - except in a set of 8.1.6 NT databases I was looking at today) whilst the state is WAITING.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

Next Seminar dates:
(see http://www.jlcomp.demon.co.uk/seminar.html )

____Denver_______December 2/4
____England______January 21/23

The Co-operative Oracle Users' FAQ
http://www.jlcomp.demon.co.uk/faq/ind_faq.html

-----Original Message-----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Date: 27 November 2002 00:36

>Dennis,
> I did some quick & dirty testing by creating a very small(10M)
>datafile with a large(2000m) autoextend clause. On the insert, the
session
>was waiting on 'file open' for most of the time. When I did a
rollback and
>reinserted the data, there were no waits (that I saw) on file open.
>
> Interestingly, this wait event does not appear to be accurately
>tracked in v$session_event. In v$session_wait the seconds in wait
(last
>trapped) was 132. In v$session_event, it shows 0. Okay, gurus, why?
Am I
>missing something in this?
>
>select * from v$session_wait where sid = 14
> SID SEQ# EVENT
>---------- ----------
>----------------------------------------------------------------
>P1TEXT

P1
>P1RAW
>---------------------------------------------------------------- ----

>----------------
>P2TEXT

P2
>P2RAW
>---------------------------------------------------------------- ----

>----------------
>P3TEXT

P3
>P3RAW WAIT_TIME SECONDS_IN_WAIT
>---------------------------------------------------------------- ----

>---------------- ---------- ---------------
>STATE
>-------------------
> 14 322 file open
>fib

4327126592
>0000000101EAB640
>iov

4327069760
>0000000101E9D840
>0

0
>00 -1 132
>WAITED SHORT TIME
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).

Received on Wed Nov 27 2002 - 14:04:48 CST