Le Monday 14 November 2011 00:14:18, Josselin Mouette a écrit : > Le dimanche 13 novembre 2011 à 23:20 +0100, Bastien ROUCARIES a écrit : > > No it does not work like you said. We know the matrix structure, not > > the kernel. We map and unmap manually. Doing as you said is > > inneficient and trash a lot cache and so on. > > This is getting insane. Please learn how to use madvise and > posix_fadvise and let the kernel deal with paging. The kernel knows > everything about the underlying hardware; the application does not.
Yes I do it with MADV_DONTNEED when needed. And the kernel do not know when to use MADV_DONTNEED on 16MB block and as you said I have performance enhancement (but we should take in account system call cost). > > > Memory is used as a cache. This is not broken. This a valid use. > > By paging the data manually to the disk, the only thing you are > achieving is duplicating it at the time of reading/writing. Please learn > how to use memory pages and stop telling people you know better when it > is obvious you don’t know what you are talking about. Thanks -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/201111151123.12073.roucaries.bast...@gmail.com
