Hi James, It appears that in order to use hardware large page support, Linux must be running in LPAR mode. I can't find anything that says this is supported in z/VM. Hopefully someone can correct me if I'm wrong. I can confirm that on a z10 under z/VM 6.1 I also do not see 'edat' in /proc/cpuinfo, so hugepage support is emulated in software.
See here: http://linuxvm.org/present/SHARE111/S9262ms.pdf (see slide 11) -- Brad Hinson <bhin...@redhat.com> Worldwide System z Sales, Strategy, Marketing Red Hat, Inc. +1 (919) 360-0443 http://www.redhat.com/z On Sep 1, 2011, at 11:31 AM, CHAPLIN, JAMES (CTR) wrote: > I am currently looking at the HugePage support feature and whether it > can help us at our site. But I hit a roadblock that someone out there > may be able to help me with. > > > > In the doc I have found (both from RH and a collection of other > presentations on the web), I have found how to set the > /proc/sys/vm/nr_hugepages value with sysctl with no problem. But my > concern is with the next bit of information concerning whether the > hardware has large page support and if not, how do I enable that > support. When I issue cat /proc/cpuinfo, we do not have the "edat" value > set in features (page 26 in > http://zjournal.tcipubs.com/issues/zJ.DEC-JAN09.pdf). We have two z196s > with zVM 6.1 running zLinux guests using RHEL 5.6 (2.6.18-238.9.1.el5). > > > > Can anyone point me to how to get the feature "edat" turned on and where > documentation on this may be located? > > > > James Chaplin > > Systems Programmer, MVS, zVM & zLinux > > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu 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/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu 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/
