Re: Calling Program information

[Vern Hamberg <vhamberg@xxxxxxxxxxx>]

Also look at Rick Turner's classic articles on batch performance at

http://www-01.ibm.com/support/docview.wss?uid=nas1e907e76673a614dd86256a290054f546

This includes the tip to turn on commitment control in order to get a 
kind of journal caching. You don't have to rollback or commit - just 
start commitment control before running a program that uses a journaled 
file - journal writes will be asynchronous, much as the LPP does. Tip 
has been around for probably at least a decade.   ;-)

HTH
Vern

Charles Wilt wrote:
> Just to be clear,
>
> Journalling + commitment control + "Soft Commit" = awesome :)
> Journalling + commitment control = good
> Journalling by itself = can be ok, but the performance (by default) it
> is definitely noticeable on batch processes even on today's
> processors.  Mainly because processor doesn't matter, disk speed is
> the big factor.
>
> I say "by default" because IBM has a LPP that you can pay for to
> improve the situation.  That allows you to turn on "journal caching"
> when you don't use commitment control.
>
> Note that the "Soft Commit" option mentioned is new to v5r4 and brings
> the benefits of journal caching to smaller commit transactions.
> Standard journalling + commitment control performs best the closer you
> can get your transactions to 128KB of data.
>
> I highly reccommend the redbook "Striving for Optimal Journal
> Performance on DB2 Universal Database for iSeries"
> http://www.redbooks.ibm.com/abstracts/sg246286.html?Open
>
> And the technote "Soft Commit: Worth a Try on IBM i5/OS V5R4"
> http://www.redbooks.ibm.com/abstracts/tips0623.html
>
> HTH,
> Charles
>
>
> On Thu, Mar 5, 2009 at 1:18 PM, Peter Connell
> <Peter.Connell@xxxxxxxxxxxxxxxxx> wrote:
>   
> > We journal everthing to be sent to a DR box.
> > Even with everything journalled the performance is very good with today's processors.
> > For 1 file. You won't even notice it.
> > You can restrict the size of that the journal will reach before the system detaches it and starts another and have some job remove detached journals.
> >
> > Peter
> >
> >
> >