13 Jul
2006
13 Jul
'06
7:15 p.m.
On Fri, 2006-07-14 at 00:56 +0400, Dmitry Baikov wrote:
If you need to stream a file, mmap'ed variant will
eat memory up to
file size. Given large enough file, it will eat all you memory and
then will begin to page out unused portions of the file.
Of course, details on when and where will vary depending on VM-system
implementation.
The thing is, you really need only a small portion of a file. Memory
mapping is useful if you need all data to be (virtually) present in
RAM.
moreover, in 2001-2002, it was actually slower to do i/o this way. when
asked about linus said "i know and i intend to keep it that
way" (paraphrasing).
--p