Re: PX Deq Credit: send blkd
- From: Martin Klier <usn@xxxxxxxxx>
- To: Oracle-L Freelists <oracle-l@xxxxxxxxxxxxx>
- Date: Fri, 19 Sep 2008 18:13:40 +0200
Hi,
Christo Kutrovsky schrieb:
> So you have diagnosed that most of the consumers's processes are using 100%
> CPU?
There is only one of them, and it's using 99% CPU on a single core of eight.
> In that case it seems like you should increase your DOP.
Yes, I agree. That's why I asked
"How can I make it parallel on WRITING side of the statement?"
initially. :)
How can I do that?
Except:
- with setting hints
- alter session enable parallel DML/DDL [parallel 32]
- alter session force parallel DML/DDL [parallel 32]
because this is what I tried so far to make the producers parallelize at
all.
But having one process writing and four processes delivering data, makes
the latter wait a lot.
My break-even is to have a parallelsm of 2 at the moment, sad on a box
with 8 CPUs and the ability to write 1000MB/s on disks. PARALLEL up to
64 just generates a nicely scalable wait ebvent list, just as reminder,
it was "PX Deq Credits: send blkd".
> btw, are you using hugepages?
Yes and no, I tried both setups so far.
Regards
Martin
--
Usn's IT Blog for Linux, Oracle, Asterisk
http://www.usn-it.de
--
//www.freelists.org/webpage/oracle-l
Other related posts:
