Messages in this thread | | | Date | Mon, 16 Jan 2012 17:43:34 +0200 | From | Avi Kivity <> | Subject | Re: Extermeley large PageTables over 500G on kernel 2.6.32.49 (SLES11 SP1) |
| |
On 01/13/2012 07:20 AM, Borzenkov, Andrey wrote: > > > 1. PTE is 8 bytes per page, which is 4K which gives 2K per 1M of memory > > > 2. All processes sharing the same shared memory share the same page > > table > > > > > > So page table for Oracle SGA 500G would be around 1G and shared by all > > Oracle clients. Is my assumption incorrect? > > > > > > > The second assumption is incorrect. So fully populated the 2000 > > processes would consume 2T; they just haven't accessed all the SGA yet. > > > > Does kernel ever free allocated page tables, or once allocated they stick for the process lifetime?
munmap() will free them, but that doesn't apply here. Linux doesn't swap page tables.
-- error compiling committee.c: too many arguments to function
| |