Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
Home -> Community -> Usenet -> c.d.o.server -> Re: log file sync + latch free WAITs
In our last gripping episode Vitaliy Mogilevskiy
<vit100gain_at_hotmail.com> wrote:
> I got a problem where a session WAIT's for "log file sync" + "latch
> free" forever and REDO LOGS never get switched. If I manually switch
> the logs (ALTER SYSTEM SWITCH LOGFILE) the "switch" succeeds but it
> doesn't help the session WAITs.
>
> V$SESSION_WAIT (waits are either "latch free" or "log file sync"
> ================================================================
> EVENT P1TEXT P1
> ------------------------- ------------------------- ---------
> log file sync buffer# 38
>
> EVENT P1TEXT P1
> ------------------------- ------------------------- ---------
> latch free address 805363076
>
> When "log file sync" waits occur P1 increments by 1 with intervals of
> 3-5 seconds then eventually "latch free" wait occurs (P1 for "latch
> free" is always same = 805363076). Below is the summary for
> waits/timeouts.
>
> V$SESSION_EVENT
> ==================================================
> SQL> /
>
> SID EVENT TOTAL_WAITS
TOTAL_TIMEOUTS
>
> --------- ----------------------------------- ----------- ------------
--
>
> 23 latch free 1618
957
>
> 23 process startup
4 0
>
> 23 rdbms ipc reply
29 0
>
> 23 enqueue
18 0
>
> 23 free buffer waits
14 0
>
> 23 local write wait
3 0
>
> 23 log buffer space
568 0
>
> 23 log file switch completion 259
27
>
> 23 log file sync 116801
212
>
> 23 db file sequential read
355 0
>
> 23 db file scattered read
396 0
>
> 23 file open
6 0
>
> 23 SQL*Net message to client
87 0
>
> 23 SQL*Net message from client
87 0
>
> 23 PX Deq: Join ACK
27 0
>
> 23 PX Deq: Signal ACK 27
12
>
> 23 PX Deq: Parse Reply
17 0
>
> 23 PX Deq: Execute Reply
1401 0
>
> 18 rows selected.
>
> Please help guys! Never seen this before.
>
>
Oracle release, O/S vendor and release information please.
-- David Fitzjarrell Oracle Certified DBA Sent via Deja.com http://www.deja.com/Received on Tue Jan 30 2001 - 15:04:18 CST