Enabling DAOS on a database – new recommendation
February 5, 2010 – 8:45 amAlmost one year ago, I wrote about “How To Wast Space” when enabling DAOS on an application. And I assumed that it might not be sure that the compact task will always do the recompress BEFORE the attachments are moved to the DAOS repository.
The recommended way to enable DAOS on an application and recompress attachments was:
- load compact mail\example.nsf -c -ZU -DAOS ON
According to IBM technote #1411563, the new recommendation is to perform 2 compacts.
First, enable compression and then enable DAOS. This is critical for customers which have upgraded from 6.5x to 8.5
- load compact mail\example.nsf -c -ZU
- load compact mail\example.nsf -c -DAOS ON
If you want to get the most out of DAOS, this is the way to do it.
btw. the IBM technote obviously has a typo. See the mistake?
4 Responses to “Enabling DAOS on a database – new recommendation”
Yes,
they missed the “On”.
By the way, what would you recommend about switching the Data- and Design-Compressing on (During the first or during the second task)?
By Harald Wolf on Feb 5, 2010
Well, I would add a third step.
load compact mail\example.nsf -c -n -v
before or after the
load compact mail\example.nsf -c -ZU
By Ulrich Krause on Feb 5, 2010
The -n -v can be added to the second compact that is doing the -daos on. The reason we recommend splitting the -ZU out to its own compact is that the performance is actually better to do the LZ1 compression by itself before storing objects in DAOS. The design/data compression will perform the same whether you bundle them with DAOS enablement or not.
By Jon Champlin on Feb 5, 2010
Jon, what type of performance are we talking about here?
By Darren Duke on Feb 6, 2010