Yep. Simple example: Even though it seems to be sometimes a little on the 'random' side, the ELAPSED_TIME column on V$SQL in v9 is an absolute god send...
Cheers Connor --- Mogens_N�rgaard <[EMAIL PROTECTED]> wrote: > And I think it's important to realise that ratios > are useless as a > starting point in the tuning process on any system, > not only Oracle. > Most OS'es and databases use not instrumented > correctly to deal with > response time measurements (makes you wonder: If > response TIME is what > matters, how can you then not measure exactly that - > time?) - so in the > other worlds (Unix, VMS, Windows, SQL Server, MySQL, > DB2....) people > still beleive in the ratios because they have > nothing better. > > Mogens > > Anjo Kolk wrote: > > >BCHR tuning is useless as a starting point in the > tuning process. > > > >Anjo. > > > >-----Original Message----- > >Yong Huang > >Sent: Wednesday, December 24, 2003 6:09 PM > >To: Multiple recipients of list ORACLE-L > > > > > >[This message is not technical, but educational. > Readers interested in > >technical info only may want to skip] > > > >Hi, Cary and Gopal, > > > >My last message is misunderstood. Nowadays most > DBAs that still use > >buffer cache hit ratio as a primary performance > tuning method are those > >that rarely browse public forums. When we convince > them that's a wrong > >method, we should not say "Look. I can bump up BCHR > to an arbitrary > >value". If he doesn't think, he'll say "Indeed. If > I can get any value, > >it must be rubbish". But if he's a logical person > and thinks for a few > >minutes, he'll say "It's unfair to run that > choose_a_hit_ratio program > >to get an arbitrary hit ratio and say the method is > wrong, because you > >can use the same logic to write a program to get an > arbitrary library > >cache hit ratio, OS in-core inode cache hit ratio > or directory name > >cache hit..." > > > >My last message is not meant to revive the outdated > and probably never > >correct tuning method. Instead it's meant to let > oracle-l members know > >that when you need to convince those DBAs that > still use that method, > >you need to accuse the BCHR method for correct > reason, namely, BCHR does > >not contain sufficient information for tuning, not > because you can raise > >its value by constantly scanning a table in Oracle; > you won't be able to > >convince some stubbon DBAs who enjoy thinking in a > quiet place. > > > >I agree that "It's not the ratio that needs > condemning, it's the advice > >about..." What I disagree is the wrong educational > tool people on public > >forums have recently used again and again to show > the inadequacy of the > >BCHR tuning method. > > > >Yong Huang > > > >__________________________________ > >Do you Yahoo!? > >New Yahoo! Photos - easier uploading and sharing. > >http://photos.yahoo.com/ > > > > > > -- > Please see the official ORACLE-L FAQ: > http://www.orafaq.net > -- > Author: =?ISO-8859-1?Q?Mogens_N=F8rgaard?= > INET: [EMAIL PROTECTED] > > 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: [EMAIL PROTECTED] (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). ===== Connor McDonald web: http://www.oracledba.co.uk web: http://www.oaktable.net email: [EMAIL PROTECTED] "GIVE a man a fish and he will eat for a day. But TEACH him how to fish, and...he will sit in a boat and drink beer all day" ________________________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: =?iso-8859-1?q?Connor=20McDonald?= INET: [EMAIL PROTECTED] 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: [EMAIL PROTECTED] (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).
