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Date: Thu, 19 Jan 2012 11:05:49 +0200
From: Ronen Hod <rhod@redhat.com>
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To: Pekka Enberg <penberg@kernel.org>
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Subject: Re: [RFC 1/3] /dev/low_mem_notify
References: <1326788038-29141-1-git-send-email-minchan@kernel.org> <1326788038-29141-2-git-send-email-minchan@kernel.org> <CAOJsxLHGYmVNk7D9NyhRuqQDwquDuA7LtUtp-1huSn5F-GvtAg@mail.gmail.com> <4F15A34F.40808@redhat.com> <alpine.LFD.2.02.1201172044310.15303@tux.localdomain> <84FF21A720B0874AA94B46D76DB98269045596AE@008-AM1MPN1-003.mgdnok.nokia.com> <CAOJsxLGiG_Bsp8eMtqCjFToxYAPCE4HC9XCebpZ+-G8E3gg5bw@mail.gmail.com> <84FF21A720B0874AA94B46D76DB98269045596EA@008-AM1MPN1-003.mgdnok.nokia.com> <CAOJsxLG4hMrAdsyOg6QUe71SPqEBq3eZXvRvaKFZQo8HS1vphQ@mail.gmail.com> <84FF21A720B0874AA94B46D76DB982690455978C@008-AM1MPN1-003.mgdnok.nokia.com> <4F175706.8000808@redhat.com> <alpine.LFD.2.02.1201190922390.3033@tux.localdomain>
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On 01/19/2012 09:25 AM, Pekka Enberg wrote:
> On Thu, 19 Jan 2012, Ronen Hod wrote:
>> I believe that it will be best if the kernel publishes an ideal number_of_free_pages (in /proc/meminfo or whatever). Such number is easy to work with since this is what applications do, they free pages. Applications will be able to refer to this number from their garbage collector, or before allocating memory also if they did not get a notification, and it is also useful if several applications free memory at the same time.
>
> Isn't
>
> /proc/sys/vm/min_free_kbytes
>
> pretty much just that?
>
>             Pekka

Would you suggest to use min_free_kbytes as the threshold for sending low_memory_notifications to applications, and separately as a target value for the applications' memory giveaway?

Thanks, Ronen.