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Date:   Thu, 18 Jul 2019 11:39:32 +0000
From:   Christopher Lameter <cl@linux.com>
To:     Waiman Long <longman@redhat.com>
cc:     Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Michal Hocko <mhocko@kernel.org>,
        Roman Gushchin <guro@fb.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shakeel Butt <shakeelb@google.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>
Subject: Re: [PATCH v2 2/2] mm, slab: Show last shrink time in us when
 slab/shrink is read
In-Reply-To: <20190717202413.13237-3-longman@redhat.com>
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References: <20190717202413.13237-1-longman@redhat.com> <20190717202413.13237-3-longman@redhat.com>
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On Wed, 17 Jul 2019, Waiman Long wrote:

> The show method of /sys/kernel/slab/<slab>/shrink sysfs file currently
> returns nothing. This is now modified to show the time of the last
> cache shrink operation in us.

What is this useful for? Any use cases?

> CONFIG_SLUB_DEBUG depends on CONFIG_SYSFS. So the new shrink_us field
> is always available to the shrink methods.

Aside from minimal systems without CONFIG_SYSFS... Does this build without
CONFIG_SYSFS?