Our TSM setup is not nearly as large as most of yours, but for what it's
worth, here are our values for the past month:

FULL_DBBACKUP          2004-08-14                               6537600
FULL_DBBACKUP          2004-08-15                               6051600
FULL_DBBACKUP          2004-08-16                               6303600
FULL_DBBACKUP          2004-08-17                               5511600
FULL_DBBACKUP          2004-08-17                              12970800
FULL_DBBACKUP          2004-08-18                               6739200
FULL_DBBACKUP          2004-08-19                               7081200
FULL_DBBACKUP          2004-08-20                               7657200
FULL_DBBACKUP          2004-08-21                               7927200
FULL_DBBACKUP          2004-08-22                               7945200
FULL_DBBACKUP          2004-08-23                               5875200
FULL_DBBACKUP          2004-08-24                               6343200
FULL_DBBACKUP          2004-08-25                               7992000
FULL_DBBACKUP          2004-08-26                               5904000
FULL_DBBACKUP          2004-08-27                               8514000
FULL_DBBACKUP          2004-08-28                               7419600
FULL_DBBACKUP          2004-08-29                               5922000
FULL_DBBACKUP          2004-08-30                               6379200
FULL_DBBACKUP          2004-08-31                               7578000
FULL_DBBACKUP          2004-09-01                               8089200
FULL_DBBACKUP          2004-09-02                               7473600
FULL_DBBACKUP          2004-09-03                               5533200
FULL_DBBACKUP          2004-09-04                               5644800
FULL_DBBACKUP          2004-09-05                               8298000
FULL_DBBACKUP          2004-09-06                               6627600
FULL_DBBACKUP          2004-09-07                               6937200
FULL_DBBACKUP          2004-09-08                               6778800
FULL_DBBACKUP          2004-09-09                               8236800
FULL_DBBACKUP          2004-09-10                               8859600
FULL_DBBACKUP          2004-09-11                               8974800
FULL_DBBACKUP          2004-09-12                               5958000
FULL_DBBACKUP          2004-09-13                               8762400


EXPIRATION             2004-08-14                               9637200
EXPIRATION             2004-08-15                              20984400
EXPIRATION             2004-08-16                               8056800
EXPIRATION             2004-08-17                              19476000
EXPIRATION             2004-08-18                               7131600
EXPIRATION             2004-08-19                              18943200
EXPIRATION             2004-08-20                              14011200
EXPIRATION             2004-08-21                              13417200
EXPIRATION             2004-08-22                              10011600
EXPIRATION             2004-08-23                              20188800
EXPIRATION             2004-08-24                              19026000
EXPIRATION             2004-08-25                              17978400
EXPIRATION             2004-08-26                              13017600
EXPIRATION             2004-08-27                              12211200
EXPIRATION             2004-08-28                               8910000
EXPIRATION             2004-08-29                              15472800
EXPIRATION             2004-08-30                              19191600
EXPIRATION             2004-08-31                              17380800
EXPIRATION             2004-09-01                              11451600
EXPIRATION             2004-09-02                              11592000
EXPIRATION             2004-09-03                              11980800
EXPIRATION             2004-09-04                              12006000
EXPIRATION             2004-09-05                              12412800
EXPIRATION             2004-09-06                              13010400
EXPIRATION             2004-09-07                              18284400
EXPIRATION             2004-09-08                              14076000
EXPIRATION             2004-09-09                              12236400
EXPIRATION             2004-09-10                              12283200
EXPIRATION             2004-09-11                              10602000
EXPIRATION             2004-09-12                              12808800

RedHat Enterprise Linux 3.2.3-34 SMP
TSM 5.2.2.4
IBM x335 Dual 2GHz Intel Xeon 2.5GB RAM
DB Size 3G (65% util - 99.7% Hit ratio) on mirrored 36G 15k disk volume
L3583-36 w/2 LTO-1 drives (dedicated FC HBA through SAN)

I think cache hit ratio would have a pretty strong correlation to expiration
performance... (having a database that's relatively tiny doesn't hurt either
;-)

Ken Mueller
Magna Carta Companies