Re: log buffer space vs. redo log space requests

In article <ip7R6.748$m76.424872_at_news20.bellglobal.com>, "Scott says...
>
>I am a little confused as to the values I am getting from these two
>statistics.
>
>log buffer space in V$SYSTEM_EVENT shows a value for waits which leads me to
>believe that the log buffer is not large enough however the redo log space
>requests from V$SYSSTAT shows a value of zero.
>
>Therefore one stat tells me there is not enough space while the other tells
>me everything is ok. I think I am misinterpreting these statistics. Can
>someone set me straight.
>
>Oracle 8.1.6 running on solaris.
>
>thanks,
>Scott.
>
>
>
>

log buffer space is a wait for space in the redo log buffer (in the SGA). you'll get this when your log buffer is too small or LGWR is not able to empty it fast enough (slow IO)

redo log space is a wait for space in the physical online redo log file (on disk). you might get this on a "checkpoint not complete".

The are somewhat un-related.

Thomas Kyte (tkyte_at_us.oracle.com) Oracle Service Industries Howtos and such: http://asktom.oracle.com/ http://asktom.oracle.com/~tkyte/ Oracle Magazine: http://www.oracle.com/oramag Opinions are mine and do not necessarily reflect those of Oracle Corp Received on Wed May 30 2001 - 12:38:58 CDT