Dave

Completely agree!

Ken

Kenneth A. Bloom
CEO
Avenir Technologies Inc
/d/b/a Visara International
203-984-2235
[email protected]
www.visara.com


> On May 19, 2018, at 1:18 PM, Gibney, Dave <[email protected]> wrote:
> 
> Why is it a pain to write "lots"  of virtual tapes. I turned all stacking off 
> and defined x1-99999 in my tape pools when we moved away from cartridges. 
> Never looked back
> 
>> -----Original Message-----
>> From: IBM Mainframe Discussion List <[email protected]> On
>> Behalf Of Brian Westerman
>> Sent: Saturday, May 19, 2018 2:52 AM
>> To: [email protected]
>> Subject: Re: VTL as 3490 vs 3590
>> 
>> 3590's are "easier" to deal with if you use HSM at all, 3490's have to be 
>> set up
>> as a percentage of the 3490 capacity, (otherwise you get something like
>> 800MB tapes (to HSM).   While the VTS could care less, it is a pain to have
>> HSM writing 600 tapes a day.
>> 
>> Several sites (about 1/3) we support are using VTL's as 3490's but most are
>> defined as 3590's.  The actual numbers are (out of 117 sites with VTL's) 36 
>> are
>> defined as 3490's although almost all of them use a larger tape "size" (some
>> (most) are 2GB some or 5GB and a couple have no limit), whereas the rest of
>> them (81 sites) are defined as 3590's.
>> 
>> Speed-wise, I don't think there is a difference, at least not that I can 
>> tell.
>> 
>> Different VTL vendors seem to use different compression techniques so the
>> sizes vary as to how much actually fits on a tape dataset after compression
>> before it wants to load the next tape.
>> 
>> I don't agree (but no one cares) with the sites that don't specify a limit 
>> to the
>> tape size.  I think that's just asking for a problem somewhere down the line,
>> but if that's what the client wants, we will run that way.
>> 
>> If left to my own preferences, I would choose 3590 every time.  I also like
>> those VTL's that don't keep the tape/disk storage inside the device and use
>> NetApp or something similar or like EMC does where the DASD is logically
>> pretty separate.  Again, that's just a personal preference thing.
>> 
>> Brian
>> 
>> ----------------------------------------------------------------------
>> For IBM-MAIN subscribe / signoff / archive access instructions, send email to
>> [email protected] with the message: INFO IBM-MAIN
> 
> ----------------------------------------------------------------------
> For IBM-MAIN subscribe / signoff / archive access instructions,
> send email to [email protected] with the message: INFO IBM-MAIN

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN

Reply via email to