I believe it has to with the fact that PQO uses direct reads bypassing the SGA to read the object blocks and that requires to flush (checkpoint) all committed changes in the SGA (dirty buffers) of that object to make sure the PQ slaves will access the most recent version of that object.
Regards, Waleed Khedr > Hi, > > I ask this on another forum....but unfortunately got no response.... > > I am trying to find out what 'TC' enqueue are. And why a select would would > wait for TC enqueue. I beleieve they have something to do with PQO and > checkpointing...but I could not find any more details. > > Any help appreciated. > > Thanks. > > > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: Ken Heng > 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.com -- Author: 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).
