Have you tried alter session enable parallel ddl; Cheers, Ian |---------+-----------------------------> | | usn@xxxxxxxxx | | | Sent by: | | | oracle-l-bounce@fr| | | eelists.org | | | | | | | | | 19/09/2008 12:55 | | | Please respond to | | | usn | | | | |---------+-----------------------------> >--------------------------------------------------------------------------------------------------------------| | | | To: oracle-l@xxxxxxxxxxxxx | | cc: | | Subject: Re: PX Deq Credit: send blkd | >--------------------------------------------------------------------------------------------------------------| Hi again. I've got still the same problem, but I tried to simplify it, reduce it to the essentials. I tried to CREATE TABLE2 TEST PARALLEL 32 AS SELECT * FROM TEST; It works, but the 32 parallel processes are only query processes, there is only ONE writing process. Due to that, all parallel query processes are waiting with "PX Deq Credit: send blkd" How can I make it parallel on WRITING side of the statement? The bahaviour is similar or same if I do an INSERT /*+ APPEND PARALLEL(TEST2,32) */ INTO TEST2 SELECT * FROM TEST; when both sides are identically partitioned (4 partitions). Any further clues? Or known no-gos? Thanks a lot, Martin Martin Klier schrieb: > I've got massive wait events named "PX Deq Credit: send blkd". As far as > I know, that's a parallel query issue, a producer is faster then the > consumer. But thats a textbook explanantion I simply don't understand. > The obvious option, to increase PARALLEL_EXECUTION_MESSAGE_SIZE, does > not fit since it's set to the (x86_64) architecture's maximum, 64k. > > The system is rather capable, and CPU load is less than 30%, disk IO > around 100MB/s, the underlying ASM diskgroups have been successfully > tested with nearly 1GB/s. > > The query in question is a huge MERGE statement with APPEND PARALLEL > hints, a little abstracted form here: > ... -- Usn's IT Blog for Linux, Oracle, Asterisk http://www.usn-it.de -- //www.freelists.org/webpage/oracle-l This email was received from the INTERNET and scanned by the Government Secure Intranet anti-virus service supplied by Cable&Wireless in partnership with MessageLabs. (CCTM Certificate Number 2007/11/0032.) In case of problems, please call your organisation?s IT Helpdesk. Communications via the GSi may be automatically logged, monitored and/or recorded for legal purposes. For the latest data on the economy and society consult National Statistics at http://www.statistics.gov.uk ********************************************************************************* Please Note: Incoming and outgoing email messages are routinely monitored for compliance with our policy on the use of electronic communications ********************************************************************************* Legal Disclaimer : Any views expressed by the sender of this message are not necessarily those of the Office for National Statistics ********************************************************************************* The original of this email was scanned for viruses by the Government Secure Intranet virus scanning service supplied by Cable&Wireless in partnership with MessageLabs. (CCTM Certificate Number 2007/11/0032.) On leaving the GSi this email was certified virus free. Communications via the GSi may be automatically logged, monitored and/or recorded for legal purposes. -- //www.freelists.org/webpage/oracle-l