RE: Full save to virtual tape?

I'll have 15K HDD. I couldn't justify the higher purchase price for SSD's, plus we keep hardware past the warranty period so maintenance costs would have been a killer.



-----Original Message-----
From: Steinmetz, Paul via MIDRANGE-L [mailto:midrange-l@xxxxxxxxxxxxxxxxxx]
Sent: Monday, March 04, 2019 1:19 PM
To: 'Midrange Systems Technical Discussion' <midrange-l@xxxxxxxxxxxxxxxxxx>
Cc: Steinmetz, Paul <PSteinmetz@xxxxxxxxxx>
Subject: RE: Full save to virtual tape?

I also use LTO7.
My disks are the most busy during a save.
Disk response increases 8x or more.

Your DASD subsystem also is a major factor.
On our old P7 R&D LPAR with 10k spinny disks, backing up to LTO7, the disks could not keep up with the LTO7 tape, disk response time now also included wait time.

We're now on P9, 100% SSD, both LPARS.
Disk response time is still 8x during a save.

A while back I tested Virtual tape.
As Rob stated, it was slower, the disks were super busy.

Paul