[svn:fx-trunk] 7830: Update ASDoc on the new backgroundFrameRate property to WindowedApplication , to by default reduce the CPU usage in cases where an app is not 'active'.

Question

Revision: 7830
Author:   [email protected]
Date:     2009-06-14 15:57:29 -0700 (Sun, 14 Jun 2009)
Log Message:
Update ASDoc on the new backgroundFrameRate property to WindowedApplication, to by default reduce the CPU usage in cases where an app is not 'active'.
Bugs: SDK-21135
Reviewer:
QE Notes:
Ticket Links:
    http://bugs.adobe.com/jira/browse/SDK-21135
Modified Paths:
    flex/sdk/trunk/frameworks/projects/airframework/src/mx/core/WindowedApplication.as
    flex/sdk/trunk/frameworks/projects/airframework/src/spark/components/WindowedApplication. as

Answer 1

By the way, I agree with sybrand: you need to tune
your redo log size.
Regards
Ignacio
http://oracledisect.blogspot.com
Ignacio,
The excessive waits on log file parallel write and the related client wait of log file sync may be due to insufficient CPU availability, and may not point at an actual redo log size problem or a problem with the disk speed where the redo is written to disk, especially if there are 3 Oracle instances on the server with a single CPU.
Paraphrased from "Optimizing Oracle Performance":
The log file sync wait event is one of the first events to show increased latencies due to the time a process spends waiting in a CPU wait queue while processing excessive logical IOs.
Kevin Closson wrote a couple blog entries that examined the potential problems of insufficient CPU capacity and its effects on log file parallel write when writing to solid state disks, and even when writing redo was explicitly disabled:
http://kevinclosson.wordpress.com/2007/07/21/manly-men-only-use-solid-state-disk-for-redo-logging-lgwr-io-is-simple-but-not-lgwr-processing/
"Once LGWR loses his CPU it may be quite some time until he gets it back. For instance, if LGWR is preempted in the middle of trying to perform a redo buffer flush, there may be several time slices of execution for other processes before LGWR gets back on CPU..." Fix the CPU problem, and the other significant waits may decrease.
JesusLuvR,
yingkuan's suggestion to look at the SQL statement that performs the 4,365,564 logical IOs, consumes 186.03 CPU seconds, and has an execution time of 225.06 seconds, is likely a very good starting point. You might also want to check the value of the SESSION_CACHED_CURSORS parameter to see if it needs to be adjusted.
Charles Hooper
IT Manager/Oracle DBA
K&M Machine-Fabricating, Inc.