How about Xen? IBM seems to be starting to push it as a virtualization technology on Intel.
> -----Original Message----- > From: Linux on 390 Port [mailto:[EMAIL PROTECTED] Behalf Of > Adam Thornton > Sent: Thursday, February 10, 2005 3:24 PM > To: [email protected] > Subject: Re: [LINUX-390] Why Zseries > > > On Feb 10, 2005, at 1:27 PM, Doug Fairobent wrote: > > > Doesn't VMware on Intel provide the same advantage as z/VM when > > compared to > > discrete servers? In the case where there is no z/OS > system (so that > > data > > sharing and communicating with z/OS are moot) why use z/VM > instead of > > VMware? > > > Sort of. > > VMware has much higher overhead than z/VM, because the x86 > architecture > was not designed with self-virtualization in mind. VMware cannot > consolidate nearly as many servers onto a single frame as Linux under > z/VM can. VMware does not provide nearly the level of granularity in > terms of guest performance tuning that z/VM does. VMware's image > management, though improving fast, is nowhere near what z/VM can do. > > On the other hand, VMware is a lot cheaper and runs on much cheaper > hardware. One of the best uses for it is actually not consolidation, > but isolation of an application from the vagaries of the hardware. > Upgrading a Windows server essentially means a total reinstall, first > of the OS, and then of any applications, because the OS is so > ridiculously dependent on stupid things like motherboard chipset, > flavor of northbridge, and just what variant of the Pentium > you've got. > On the other hand, if you have VMware on the box, then when you > upgrade the hardware you just reinstall the OS and VMware (which is a > very simple app to configure) (we'll assume VMware ESX counts as both > the OS and VMware for this case), and then fire up your VMware > containers (and maybe increase their memory size--Windows CAN handle > that without a reinstall) and you've just gotten the speed benefits of > your upgrade, without having to mess with application configuration. > > Adam > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to [EMAIL PROTECTED] with the message: INFO > LINUX-390 or visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -------------------------------------------------------- If you are not an intended recipient of this e-mail, please notify the sender, delete it and do not read, act upon, print, disclose, copy, retain or redistribute it. Click here for important additional terms relating to this e-mail. http://www.ml.com/email_terms/ -------------------------------------------------------- ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
