On 15 August 2013 17:34, Mauro Souza <thoriu...@gmail.com> wrote:
> You can safely ignore the cache usage on Linux, zVM will realise the page > was not in use and drop it itself. When Linux needs memory, it will reclaim > cache pages automatically. > > So we disagree. Maybe we wouldn't if you had read the page that I linked to. The point that you miss is when Linux needs memory and reclaims a page frame from page cache, z/VM will first bring back the old contents that Linux did not care about anymore. This is where getting a free page will slow you down. Especially since the LRU patterns interfere. The idea is that you want to drop the backing page from z/VM either before it is paged out or before z/VM will page it back in. If you have CMMA enabled, then having Linux free the page (by drop_caches) will prevent z/VM from paging it out. Rob ---------------------------------------------------------------------- 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/
