Original Message:
Sent: Mon May 29, 2023 08:45 AM
From: Denis Augusto Pereira
Subject: How to size cache capacity?
Hi Glenn,
Sorry about my delay, busy weeks =)
How do I ask customer to collect this report? And, after collect, it is necessary only to sum the number of all written tracks?
Thank you.
------------------------------
Denis Augusto Pereira
Original Message:
Sent: Tue May 16, 2023 12:27 PM
From: Glenn Wilcock
Subject: How to size cache capacity?
Hey Denis,
The DFSMShsm SMF records can be used to determine the amount of data being written during DFSMShsm migration processing. (Backup should not be included in the study because HSM Backup does not yet support TCT). FSRTYPE=3 is migration to tape and FSRTRKW (FSRF32K=0) and FSRTRKKW (FSRF32K=1) report the number of tracks written. The TCT performance test used data with about 4:1 compression, but I would recommend a more conservative number. Maybe 3:1?
------------------------------
Glenn Wilcock
Original Message:
Sent: Mon May 15, 2023 10:50 AM
From: Denis Augusto Pereira
Subject: How to size cache capacity?
Hello Experts,
Please, I'm working in a TCT implementation and I would like to ask a question related to the impact of cache (capacity) utilization.
My customer is concerned about the capacity who HSM will consume and I would like support of how to size properly it.
According to the Batch Magic output, looks like customer will need around 8 TBs (30 days - HSMML2 and HSMBAK), but, the Business Partner create a job to read the HSM data and the output was very different, around 150 TBs.
Although I know the possibility of do data compression by the DS8900, I need to understand how to estimate the cache utilization.
Is there a way to estimate the capacity? If yes, please, how to do that? Is there a compression rate that I can work?
Thanks in advance.
------------------------------
Denis Augusto Pereira
------------------------------