?Can Linux (or Win?) replace AIX for hosting an I/O intensive TSM service?

After scanning the past year's ADSM-L postings including Linux in the subject
I have the impression that a few people are playing with Linux hosting a TSM
service, but real I/O intensive TSM services are still mainly hosted by AIX.

?Is anyone already using or actively planning to use Linux (RedHat EL 3.0?)
to host an I/O intensive TSM service similar to any described under the
recent ADSM-L thread, "Sizing an AIX platform and tape libraries"?

We believe we are approaching the maximum that can be achieved w/
       TSM:    v5.2.1.3
       OS:     AIX 5.1 (64bit)
       CPU:    IBM 7025-6F1 w/ 4 * 750Mhz proc's + 3GB RAM
       SAN:    1 Gb w/ EMC Symmetrix 8830
       LAN:    1 Gb Ethernet
       ATL:    IBM 3494 w/ 6 * 3590E drives
               IBM 3584 w/ 4 * 3580 LTO1 + 2 * 3580 LTO2 drives

This configuration is successfully supporting our current ITS TSM service
(see details below), but we believe we either need a major performance
boost or to split this load onto an additional host platform:
       Linux, Win*, or must we remain w/ AIX for I/O performance?
to handle expected additional growth.

Which platform have you chosen (or would you choose) for similar TSM service?

Yale ITS TSM Service:
--------------------
       Active Clients:  2400 <= 3d, 2500 <= 7d, 2700 <= 35days

               Servers:        151
                       WinNT,2K*      105
                       Linux           20
                       Solaris          9
                       AIX              7
                       SQL-BT (Oracle)  3
                       Mac              2
                       TDP's: MSSQL,MSexchg:  2 + 1
                       [new]            2

               Personals:      2549
                       WinNT,2K*,XP  2230
                       Win98,ME        26
                       Mac            183
                       Linux           50
                       Solaris          5
                       AIX,DEC*X,HPUX,IRIX:  1 ea.
                       [new]           51

               Expected growth:  +500-600 clients for several years
                               +20% data for existing clients/year?

       TSM DB:  75.7% of 160GB
               BAckup DB w/ LTO1 HCmpr. takes 2.3h
               EXPIre Inv examines ~6M obj, deletes ~1M obj. in 8-9h


       Disk STGpools:  600 + 180GB
       Nightly Backup Period: 15:30-08:00+
       Weeknight Backup Load:  500-650GB+

Thanks for any experience/insight you are willing to share with us!
--
Jim.Owen AT Yale DOT Edu (203.432.6693)