On Fri, 2 Sep 2011 07:35:56 -0400 "CHAPLIN, JAMES (CTR)" <[email protected]> wrote:
> I almost gave up hope on HughPages due to all our zLinux Guests run > under zVM, and we like using zVM to control the swapping as best as > possible. I do have two follow-up questions: > > 1) Can you point me to any reference material dealing with HugePages > with zVM (v6.1) where I can start my "homework" on the topic? I did a > search online of IBM zVM 6.1 doc on HugePages, Large Pages and came up > with nothing. There is no documentation for z/VM as the edat facility is not supported. The emulation for large pages takes place in the Linux guest. > 2) What is required or needs to be done to enable edat in zLinux from > the zVM side? Again, would you be able to point me to any doc in the zVM > side? How do we get the "edat facility", is it hardware or a setting in > either the SE or HMC with the LPAR definition, or in the IODF? You cannot enable the edat facility under z/VM for a Linux guest (and you won't see "edat" in the cpu features) but you can still use large pages in the Linux guest. Just specify the hugepages=<nr> kernel parameter. The Linux kernel will automatically use the large page emulation if the edat facility is missing. You may want to look at the "Large Page Support" chapter in "Linux on System z Device Drivers, Features and Commands": http://public.dhe.ibm.com/software/dw/linux390/docu/lk39dd11.pdf -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. ---------------------------------------------------------------------- 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 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
