In my exerience the delay of staging a virtual tape to cache is mainly determined by mounting the physical tape on the physical unit and positioning to the location of the virtual volume. Reading then 1GB or 4GB into the cache makes minor differences in the total virtual volume recall time.
Kees. "Darth Keller" <[email protected]> wrote in message news:<of74e9ac9d.68c78cd8-on862575ee.004539e7-862575ee.00457...@assurant .com>... > Have you thought about defining different sized virtual tapes and possibly > using a larger tape for ML2? > > Of course as some else pointed out, large tapes would mean having to stage > more data back into the VTS buffer for any recall from a tape not already > in the buffer. Must be some way to figure out what the optimum size would > be. > > ddk > > > > > > > > Wayne Bileci <[email protected]> > Sent by: IBM Mainframe Discussion List <[email protected]> > 07/08/2009 05:59 PM > Please respond to > IBM Mainframe Discussion List <[email protected]> > > > To > [email protected] > cc > > Subject > DFHSM Native 3590 tapes to virtual 3490E's > > > > > > > We will be migrating DFHSM 3590 native tapes from a 3494ATL/B18 Vts > environment to a new IBM TS7700. The 3590's will be recycled via HSM onto > > virtual 3490E media type 2 volumes(4000MB) in the new VTS. My question is > - > Is this feasible to take 3590(10GB uncomressed tapes) compressed data > tapes > and move the data onto the smaller 3490E's? If my calculations are correct > we > will need 4 or 5 virtual volumes for each physical 3590 which means our > TMC > volume count will rise dramatically but I am more concerned about the > impact > to HSM and the CDS's because we will probably have more connected volume > groups. > > Thanks, > Wayne Bileci > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: GET IBM-MAIN INFO > Search the archives at http://bama.ua.edu/archives/ibm-main.html > > > ************************************************************************ ************** > This e-mail message and all attachments transmitted with it may contain legally privileged and/or confidential information intended solely for the use of the addressee(s). If the reader of this message is not the intended recipient, you are hereby notified that any reading, dissemination, distribution, copying, forwarding or other use of this message or its attachments is strictly prohibited. If you have received this message in error, please notify the sender immediately and delete this message and all copies and backups thereof. > > Thank you. > ************************************************************************ ************** > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: GET IBM-MAIN INFO > Search the archives at http://bama.ua.edu/archives/ibm-main.html ********************************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ********************************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
