I've never run out of space in a partition with file volumes but I
assume it would give an error if it tried to write to a file and had no
space.  It would then continue on to the next file etc until it found
space or ran out of files.

We are at 5.2.2.4 on Windows 2003 and have found that TSM will use all
of the predefined volumes in one partition before using ones in the
next.

Tim Rushforth
City of Winnipeg

-----Original Message-----
From: Steve Bennett [mailto:steve_bennett AT ADMIN.STATE.AK DOT US] 
Sent: Thursday, January 27, 2005 11:29 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: using sata with sequential file preallocation

Here is a question for all of you that are using large disk arrays with
stgpools using seq file type.

TSM server v5.2.3.2
Win2000

We are installing a 6tb sata raid5 array as an intermediate stgpool to
be used with sequential file type. The array will have 3 partitions of
2tb each and all files will have be preallocated because of the devclass
limitation of only using one partition dynamically. The hierarchy will
be local disk --> local attached sata --> tapepool.

Let's say I predefine 1000 files of 1gb each (1tb total out of 2tb
available) in each of the partitions and then set the devclass max
capacity to 20gb. When writing data to the intermediate stgpool TSM will
keep adding files up to 20gb each and up to 1000 files or until the
partition is full at something less than 1000 files.

With mostly 20gb files the partition will fill with about 100 files.
What happens next? Does TSM then use preallocated files in the next
available partition or does it give some sort of allocation error
because it hasn't used the 1000 files but has run out of space in the
first partition?

I guess another question might be, does TSM do some sort of round robin
use of files on the three partitions or does it use files on one
partition until it is forced to use files on the next partition?

--

Steve Bennett, (907) 465-5783
State of Alaska, Enterprise Technology Services, Technical Services
Section