On Thu, Mar 3, 2011 at 1:44 PM, Bauer, Bobby (NIH/CIT) [E] < baue...@mail.nih.gov> wrote:
We have a Wordpress server that really spikes during certain, know times of > the month, about 45000 hits/hour. Its running on a single z9 IFL with only > 4G of memory on the lpar, z/VM 5.4, REHL 6 (yeah, I know, more memory, good > luck since we are a govt. agency). The user did not expect this kind of > response so we have all been surprised. > That sounds like a good candidate for "CMM with a stick" - during know peak times you let air out of the balloon, and in the quiet periods you inflate the CMM balloon to give resource back to z/VM. Make sure to add plenty of VDISK for swap space so that memory allocation does not fail when your squeeze the penguin (the 128M isn't much on a 2G server). Something like that is also neat for services that need resources during the night when online services need less (eg TSM running backups). To determine what amount could be donated, use the "drop_caches" in an idle period to get a base level. And after some activity you review performance history to understand the peak requirement. Rob -- Rob van der Heij Velocity Software http://www.velocitysoftware.com/ ---------------------------------------------------------------------- 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/
