Oracle FAQ Your Portal to the Oracle Knowledge Grid

Home -> Community -> Mailing Lists -> Oracle-L -> Re: OPS Sequences: nocache == order ??

Re: OPS Sequences: nocache == order ??

From: Anjo Kolk <>
Date: Sat, 07 Sep 2002 00:13:19 -0800
Message-ID: <>

  1. I think that the tpc numbers are done represented in Transactons Per Minute (TPM/C) and not Per second. So event with 500000 tpm/c it means around 8000 tps.
  2. Inserting 13000 rows with direct I/O doesn't mean you did 13000 transactions. It could be one transaction
  3. I have seen the theoretical limit, but if I recall correctly it was the number of SCN numbers that was generated. That way they can calculate how long it takes before the SCN number will wrap (it is only 48 bits). That is way in the future.


On Saturday 07 September 2002 04:08, you wrote:
> One of our accelerator control system developers, an Oracle neophyte,
> claims to have achieved 13,000 tps writing to a RAID 5 array. I did set up
> the database, but most of the credit goes to him for exploring the OCI
> direct I/O options. I have no verified the rate, but I have no reason
> whatsoever to doubt him.
> This is on older four processor sun box. We've now traded in the lone
> a-1000 ,attached two T3's, and turned on archive logging. I had him retest
> and he said it was quicker than before . It's still RAID 5. If you are
> wondering why RAID 5, we have another little 659.9 Terabyte database and
> thousands of machines in compute farms to process the associated data.
> That project has first choice, and the rest of us make do with what's left.
> I too am curious where this theoretical limit of 16384 comes from.
> Theoretical as it no matter what hardware one chose this limit could not be
> surpassed?
> Ian MacGregor
> Stanford Linear Accelerator Center
> -----Original Message-----
> Sent: Friday, September 06, 2002 4:38 PM
> To: Multiple recipients of list ORACLE-L
> On Wednesday 04 September 2002 09:53, Tim Gorman wrote:
> > Thinking more about it last night...
> >
> > Since Oracle's theoretical limit is 16384 commits per second, I imagine
> > that you could safely make the sequence recycle at 9999 (or 16384 or
> > 99999) and limit the number of digits contributed by the sequence to
> > 4-5...
> Really? What have they done in the past to get those astronomical TPS
> numbers on some of their bencmarks?
> I'm pretty sure they were in excess of that number.
> IIRC, they were done on an nCube using OPS and about 400 CPUs.
> Jared

Please see the official ORACLE-L FAQ:
Author: Anjo Kolk

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
To REMOVE yourself from this mailing list, send an E-Mail message
to: (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).
Received on Sat Sep 07 2002 - 03:13:19 CDT

Original text of this message