I see you have found the answer yourself after I send out my e-mail. :) Note, there were inaccurate statistics about "opened cursors current" in some releases (sorry I forgot which 8i release it was) when PQ is in use.
Richard -----Original Message----- Sent: Thursday, August 07, 2003 5:40 PM To: Multiple recipients of list ORACLE-L I should have known to check Steve's site first (is he still lurking around here?). One thing I noticed is that one of the cursors listed in V$OPEN_CURSOR is an INSERT into AUD$. This would account for the discrepancy and could match the description you provided. So, in summary, the true number of open cursors is correct in V$SESSTAT and is *not necessarily* the count of rows in the corresponding V$OPEN_CURSOR view. And my apologies to the sticklers of the list who have noticed my "V$SESSSTAT" and "V$OPEN_CURSORS"... <sigh> Rich Rich Jesse System/Database Administrator [EMAIL PROTECTED] Quad/Tech Inc, Sussex, WI USA > -----Original Message----- > From: Tanel Poder [mailto:[EMAIL PROTECTED] > Sent: Thursday, August 07, 2003 4:20 PM > To: Multiple recipients of list ORACLE-L > Subject: Re: V$SESSSTAT stat 3 vs V$OPEN_CURSOR > > > Hi! > > This is troubleshooting, not performance tuning ;) > As far as Ixora states, v$sesstat "opened cursors current" > shows PL/SQL > cached cursors as well, even when they are explicitly closed > (assuming that > session_cached_cursors is set). > But v$open_cursor doesn't show the number of cursor > structures in UGA, but > it shows you (some kind of count) of parse locks which get > created in SGA > for a SQL statement or PL/SQL block. > They provide a link from schema objects to shared SQL area, > so the cursors > can be invalidated when doing DDL on referenced objects. They > are called > breakable parse locks in Concepts Manual. As the name says > "breakable" - > even though you got a lock on schema object, you still can > alter it, the > lock is just "broken", the cursor is invalidated (but remains > cached in UGA) > and has to be reloaded on next execution. Here we can have a > situation, when > as result of DDL, we don't have any breakable parse locks on > SGA anymore, > but we still have open cursors in UGA. Thus the difference > between v$sesstat > and v$open_cursor. > > (this story is based on Concepts manual and Ixora) > > But for ORA-1000 errors, you should maybe set event for > ORA-1000 and dump > errorstack. Or sample v$sesstat quite often (once per few > seconds), to catch > the point where number of open cursors jumps to ceiling (as I > understand, > it's fairly low normally). > > And for TAR's - I recommend you to do few Oracle Applications > upgrades, > especially to fresh versions of major new releases, such > 11.5.1 or 2, then > you start even seeing severity 1 TARs in your dreams ;) > > Tanel. > > ----- Original Message ----- > To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> > Sent: Thursday, August 07, 2003 11:14 PM > > > > No takers on this from the perf tuning gurus? Please don't > make me open a > > TAR. Think of the children... > > > > Rich > > > > Rich Jesse System/Database Administrator > > [EMAIL PROTECTED] Quad/Tech Inc, Sussex, WI USA > > > > > > > -----Original Message----- > > > From: Jesse, Rich > > > Sent: Thursday, July 24, 2003 3:39 PM > > > To: Multiple recipients of list ORACLE-L > > > Subject: V$SESSSTAT stat 3 vs V$OPEN_CURSOR > > > > > > > > > Hey all, > > > > > > We recently had a problem with a 3rd-party app getting > > > "ORA-1000 max open > > > cursors exceeded" on their 8.1.7.4 DB. Since OPEN_CURSORS is > > > set to 500 in > > > the init.ora -- should be more than generous for a tiny app > > > on a tiny DB -- > > > we started looking into how many cursors the app actually has > > > open at any > > > given time. > > > > > > While investigating this, I see that the number of rows in > > > V$OPEN_CURSORS > > > isn't consistent with the value of stat 3 ("opened cursors > > > current") of > > > V$SESSSTAT. Of the two processes I looked at, each had a > > > V$SESSSTAT value > > > of "3" for stat 3, while the first had a single entry in > > > V$OPEN_CURSOR and > > > the second had four. > > > > > > Should these values match? I looked on Metalink but was > > > unable to find any > > > reference to the relationship between these, other than a > > > forum article > > > where the OraSupport person was extraordinarily unhelpful. > > > > > > TIA, > > > Rich > > > > > > Rich Jesse System/Database Administrator > > > [EMAIL PROTECTED] Quad/Tech Inc, Sussex, WI USA -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Jesse, Rich 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). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Richard Ji 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).
