Re: [PATCH 3/3] Quick vmalloc vs kmalloc fix to the case wherearray size is too large

From: KAMEZAWA Hiroyuki
Date: Mon Jul 13 2009 - 23:55:36 EST


On Mon, 13 Jul 2009 20:50:33 -0700
Paul Menage <menage@xxxxxxxxxx> wrote:

> On Mon, Jul 13, 2009 at 4:49 PM, KAMEZAWA
> Hiroyuki<kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote:
> > IIUC, this place, .../procs interface is not so important for performance
> > as to being allowed this ugly conding.
> >
>
> It's not just the calling thread that suffers from the overhead -
> we've seen performance hits on other processes on a machine due to the
> TLB-shootdown overhead associated with vmalloc()/vfree().
>
Hmm, ok...then, if too much pids, you hit vmalloc()/vfree() problem again.
So, it's not good idea to use vmalloc/vfree here after all.

Thanks,
-Kame

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