>We're trying to determine how much space we need to allocate for the ADSM
>database (this is where all the ADSM backup version stats are kept).  We've
>heard that we need about 200 bytes for each file we backup.  At that rate,
>to backup and keep 8 versions of 1,000,000 files, we will need approximately
>1.6 GB for the database.  We'll also need another 1.6 GB to duplex the
>database, as recommended.  Are my space calculations correct?  Do you really
>need 200 bytes per backup or is this a worst case scenario number?

I believe your estimate is actually too low.  Each version of a file
will require approximately 600 bytes while each copy of the file
(cached or in copy storage pools) requires an additional 175 bytes or so.
Allow some extra for db overhead, partially-filled database pages,
and storage of data other than file data.  For the information you provided,
you should probably allow at least 6 GB for the database.  More will be
required if you use copy storage pools, database mirroring, or caching
in a disk storage pool.

Keep in mind that your database size can be reduced significantly by
reducing the number of versions that are maintained for each file.
If you need eight versions of some files, but a few number of versions
for other files, you can set up policies to achieve this.

Dave Cannon
ADSM Server Development