phk malloc, was (Re: ptmalloc2)

[Eduardo Tongson]

On Thu, 24 Feb 2005 09:14:56 +0800, David Xu <davidxu at xxxxxxxxxxxxxx> wrote:
> You will have an unusable machine if you turn on overcommit,
> when memory is about to be exhausted, any code not written by you
> will crash because they don't check if malloc will fail!

probably the reason for the description for the vm.overcommit_memory sysctl
1       -       Always overcommit. Appropriate for some scientific
                applications.

Quite OT but I found the original announcement for the overcommit accounting
http://www.uwsg.iu.edu/hypermail/linux/kernel/0207.2/1196.html
which gives a bit of background of its purpose.

> Any program and system utilities will core dump or be locked there
> if memory is exhausted, in the machine, your code only occupies
> 1/10000 or less, making 1/10000 code to be overcommit aware does not
> make sense.
> 
> Regards,
> David Xu
> 
> 


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Eduardo Tongson     
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