Re: [PATCH 0/5] mm: support parallel free of memory

Aaron Lu
2017-03-01T01:22:21Z

On 03/01/2017 08:43 AM, Dave Hansen wrote:
> On 02/28/2017 04:39 PM, Andrew Morton wrote:
>> Dumb question: why not do this in userspace, presumably as part of the
>> malloc() library? malloc knows where all the memory is and should be
>> able to kick off N threads to run around munmapping everything?
>
> One of the places we saw this happen was when an app crashed and was
> exit()'ing under duress without cleaning up nicely. The time that it
> takes to unmap a few TB of 4k pages is pretty excessive.

Thanks Dave for the answer, I should have put this in the changelog(will
do that in the next revision). Sorry about this Andrew, I hope Dave's
answer clears things up about the patch's intention.

Regards,
Aaron