To reply to the David Juarez's post, and clarify Dave Jones' reply, Dave Jones' reply is correct. It just leaves off the dynamic memory change up to the mstor (16G in the example) available via the CP DEFINE STORage command.
That dynamic change is gone the moment that userid is logged off, unless it has been matched by Dave's suggestion to update the user directory entry, presuming that a permanent change is desirable (not always the case). We've had instances in which more memory was required for a big app (read: Websphere, or Omegamon/XE) installation, but not needed after the software was installed. Permanently increasing the memory in such instances would be a "bad thing", causing extra real z/VM paging and I/O. Mike Walter Hewitt Associates Any opinions expressed herein are mine alone and do not necessarily represent the opinions or policies of Hewitt Associates. "Dave Jones" <[EMAIL PROTECTED]> Sent by: "The IBM z/VM Operating System" <[email protected]> 11/24/2008 05:20 PM Please respond to "The IBM z/VM Operating System" <[email protected]> To [email protected] cc Subject Re: How can we control how much CPU is used by each zLinux guest? Hi, David. Juarez, David T. wrote: > Thanks for the reply Mike. Ok so in your example if I logon with 2G and I do something > that requires more than 2G I would need to issue CP DEFINE STORAGE to increase my > storage above 2GB but can't request more than 16GB correct? z/VM will not dynamically > add more memory up to 16GB? > Correct. Your maximum memory size is set to 16GB, and z/VM will not automatically increase your virtual storage from 2GB to 16GB. If your application needs more than 16GB, you have to modify the USER statement in your user directory entry, and bring the modified user directory online. > > David Juarez IT Specialist > > -----Original Message----- From: The IBM z/VM Operating System > [mailto:[EMAIL PROTECTED] On Behalf Of Mike Walter Sent: Thursday, November 20, > 2008 5:29 PM To: [email protected] Subject: Re: How can we control how much CPU > is used by each zLinux guest? > > David, > > Others have already supplied the answer to how to limit a guests CPU absorption/abuse. > > But to answer the question about the "USER MSTOR parm"... I presume that you are > referring to the USER record in the USER DIRECT file (or using whichever Directory > Manager product you might have), as documented in the CP Planning and Administration > Guide. > > If so, that "mstor" is the **maximum** size to which that virtual machine can increased > with the 'CP DEFINE STORage' command. The CP DEFINE STORAGE command is dynamic, but > instantly destructive to running the virtual machine. When issued, it resets the > virtual machine, killing any running operating system. > > There are two memory sizes defined in the USER record, 'stor' and 'mstor'. > > > 'stor' defines the default memory size of the virtual machine when logged on without > any special logon operands. Lets assume that your server 'stor' size is 2G, and the > 'msize' (Max size) is 16G. > > When you logon without any special LOGON operands, the virtual machine memory size will > be 2G. > > But you may specify a size up to the 'mstor', by including the Storage operand to > logon, e.g. LOGON yoursrvr S 16G (maybe you're doing some software installation that > requires huge amounts of memory for the installation). Your server will then be > allocated 16G of memory until you logoff or change it dynamically. > > OTOH, maybe you logged on with that server's default 2G of storage and after a while > find that you temporarily need more memory for some reason. You may issue the command > 'CP DEFine STorage 16G' (or anything less) on that server, without logging off. BUT -- > when the command is issued, the running operating system in that server is killed > instantly. Better... gracefully shut it down before issuing the command, then issue > the CP IPL command as needed. > > Mike Walter Hewitt Associates Any opinions expressed herein are mine alone and do not > necessarily represent the opinions or policies of Hewitt Associates. > -- DJ V/Soft z/VM and mainframe Linux expertise, training, consulting, and software development www.vsoft-software.com The information contained in this e-mail and any accompanying documents may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient of this message, or if this message has been addressed to you in error, please immediately alert the sender by reply e-mail and then delete this message, including any attachments. Any dissemination, distribution or other use of the contents of this message by anyone other than the intended recipient is strictly prohibited. All messages sent to and from this e-mail address may be monitored as permitted by applicable law and regulations to ensure compliance with our internal policies and to protect our business. E-mails are not secure and cannot be guaranteed to be error free as they can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by e-mail.
