Re: [PATCH -mm] mm, swap: Use page-cluster as max window of VMA based swap readahead

[Huang\, Ying]

Minchan Kim <minchan@xxxxxxxxxx> writes:

> On Tue, Oct 10, 2017 at 04:50:10PM +0800, Huang, Ying wrote:
>> Minchan Kim <minchan@xxxxxxxxxx> writes:
>> 
>> > On Tue, Oct 10, 2017 at 02:08:55PM +0800, Huang, Ying wrote:
>> >> From: Huang Ying <ying.huang@xxxxxxxxx>
>> >> 
>> >> When the VMA based swap readahead was introduced, a new knob
>> >> 
>> >>   /sys/kernel/mm/swap/vma_ra_max_order
>> >> 
>> >> was added as the max window of VMA swap readahead.  This is to make it
>> >> possible to use different max window for VMA based readahead and
>> >> original physical readahead.  But Minchan Kim pointed out that this
>> >> will cause a regression because setting page-cluster sysctl to zero
>> >> cannot disable swap readahead with the change.
>> >> 
>> >> To fix the regression, the page-cluster sysctl is used as the max
>> >> window of both the VMA based swap readahead and original physical swap
>> >> readahead.  If more fine grained control is needed in the future, more
>> >> knobs can be added as the subordinate knobs of the page-cluster
>> >> sysctl.
>> >> 
>> >> The vma_ra_max_order knob is deleted.  Because the knob was
>> >> introduced in v4.14-rc1, and this patch is targeting being merged
>> >> before v4.14 releasing, there should be no existing users of this
>> >> newly added ABI.
>> >> 
>> >> Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
>> >> Cc: Rik van Riel <riel@xxxxxxxxxx>
>> >> Cc: Shaohua Li <shli@xxxxxxxxxx>
>> >> Cc: Hugh Dickins <hughd@xxxxxxxxxx>
>> >> Cc: Fengguang Wu <fengguang.wu@xxxxxxxxx>
>> >> Cc: Tim Chen <tim.c.chen@xxxxxxxxx>
>> >> Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
>> >> Reported-by: Minchan Kim <minchan@xxxxxxxxxx>
>> >
>> > It seems your script is Ccing only with Cc: tag, not other tags.
>> > Fix it so any participant of topic can get the mail.
>> 
>> I just used `git send-email`, no other scripts.  We need to fix `git send-email`?
>
> You can do it via cccmd.
>
> Just a reference:
>
> ~/bin/kcccmd
> sed -nre 's/^(Acked|Reviewed|Reported|Tested|Suggested)-by: //p' "$1"

Thanks, will use this script in the future.

Best Regards,
Huang, Ying