Re: 2.2/2.4/2.6 VMs: do malloc() ever return NULL?

["Ihar 'Philips' Filipau" <filia@softhome.net>]

Rik van Riel wrote:
> On Tue, 25 Nov 2003, Ihar 'Philips' Filipau wrote:
> 
> 
>>># echo 2 > /proc/sys/vm/overcommit_memory
>>>
>>>Then try again.
>>
>>   What do you know what is not said in docs?
>>   What '2' means?
> 
> Strict non-overcommit mode.  You can allocate as much
> non-file-backed virtual memory as will fit in swap,
> plus /proc/sys/vm/overcommit_percentage worth of memory.
> 

   [ s/overcommit_percentage/overcommit_ratio/ ]

   Thanks! On 2.6 it works as expected. Test with two concurrent memory 
allocations took some time, but both apps stops exactly when memory was 
depleted. Great.

   Did rmap has something todo with this?
   As I see from implementation of do_mmap_pgoff() - it changed from 2.4 
to 2.6 - but there are a lot of common things.
   If I will do dumb back port of this check to 2.4 - do you think it 
will work? 2.4->2.6 memory accounting changed?
   I didn't found this check in your rmap patches for 2.4.22. (btw 
thanks for keeping them up-to-date).

-- 
Ihar 'Philips' Filipau  / with best regards from Saarbruecken.
--                                                           _ _ _
  Because the kernel depends on it existing. "init"          |_|*|_|
  literally _is_ special from a kernel standpoint,           |_|_|*|
  because its' the "reaper of zombies" (and, may I add,      |*|*|*|
  that would be a great name for a rock band).
                                 -- Linus Torvalds