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Acceptable total Waits ? [message #65138] Sun, 16 May 2004 17:33 Go to next message
Messages: 91
Registered: March 2004
Hi Everyone,


I have a question regarding what is seen to be an acceptable number of total waits for particular events. I have gathered some stats below.


EVENT                                                            TOTAL_WAITS
---------------------------------------------------------------- -----------
control file sequential read                                            7483
control file parallel write                                           161288
log file sequential read                                                   8
log file single write                                                      8
log file parallel write                                                  224
log file sync                                                             14
db file sequential read                                                42651
db file scattered read                                                118986
db file parallel write                                                   145
direct path read                                                       46240
direct path write                                                        614
sort segment request                                                       1
library cache pin                                                        960


Basically, my question is, how do I know what is an acceptable number of total waits for a system for event: db file scattered read.

as an example.


Your feedback is greatly appreciated. Thanks .... IA
Re: Acceptable total Waits ? [message #65141 is a reply to message #65138] Sun, 16 May 2004 23:43 Go to previous message
Daljit Singh
Messages: 290
Registered: October 2003
Location: Texas
Senior Member

According to me before knowing the appropriate wait time u should know what is the actual meaning of the event. In ur case "db file scattered read" is really to high but if u dont know what "db file scattered read" means than you can't do anything. Like "db file scattered read" means oracle is facing waits while having multiple reads from hard disk (physical reads). There may be some hardware problem like hard disk may be too slow to process the requests.

In short very first you should know what actually this wait for? and whether it is acceptable or not? Once you get the answer of first question then getting the answer of second would be much easier.

Daljit Singh
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