I've been reading O'Reilly on this. They have an example where they used
onspaces to create a dbspace of 100000 KB, and then used onparams
for a physical log size of 50000 KB.

I'm curious why the log size is exactly half the size of the dbspace. When looking at the results through onstat -d, the space is then 50% used just
after initialization.

Anyone understand this?
Thanks for any response!

Coreysan

What exactly you don't understand?
50MB is 50% of 100MB...

The physical log is allocated in a dbspace... probably is in the dbspace that you looking for on onstat -d..

look up in onconfig the parameter PHYSDBS...


sorry my bad English...

thanks for your response. Here's what I don't understand. If I create a dbspace for the DB, the dbspace is actually empty until I load data. Once data is in, then the space is filled up.
Using that idea, when I create dbspace for physical logging, the dbspace is empty, but when I use onparams, it becomes 50% full before I populate the database with data. If its 50% full, what is it full of?
The only thing I can figure is that the onparams utility reserves page-space, and that "fills" up the dbspace, so to speak. Is that true or false?

True!

When you initialize a instance of IDS you need have in your mind 4 thinks: root, logical log, physical log and data...
- root : space to database SYSMASTER
- physical log: space reserved to before-images pages....
- logical log:: space reserved to transactions logs...
- data: your database...

By default on the first initialization the configuration put all together, but this is not recommended... at least you need a dbspace for each one.
some like this:
rootdbs - only to database sysmaster
physdbs - only to physical log (allocated with onparams)
logdbs - only to logical log (allocated with onparams)
data1dbs - only to your database

I'm sorry if my English do not help...