flush xorg image cache?
Alan Cox
alan at lxorguk.ukuu.org.uk
Wed Apr 20 09:33:52 PDT 2005
On Mer, 2005-04-20 at 17:59, Roland Mainz wrote:
> heap size - and due the implementation of most default memory allocators
> in unix/linux the heap size cannot shrink[1].
ITYM "In unix"
To quote the glibc manual on "Efficiency Considerations for 'malloc'"
--
Very large blocks (much larger than a page) are allocated with
`mmap' (anonymous or via `/dev/zero') by this implementation. This has
the great advantage that these chunks are returned to the system
immediately when they are freed. Therefore, it cannot happen that a
large chunk becomes "locked" in between smaller ones and even after
calling `free' wastes memory. The size threshold for `mmap' to be used
can be adjusted with `mallopt'. The use of `mmap' can also be disabled
completely.
--
So for the Linux case mallopt should be all you need to touch.
Alan
More information about the xorg
mailing list