From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
To: Waiman Long <longman@redhat.com>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-mm@kvack.org, Alexander Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH RFC 1/8] dcache: show count of hash buckets in sysctl fs.dentry-state
Date: Fri, 8 May 2020 19:16:40 +0300 [thread overview]
Message-ID: <ac1ece33-46ea-175a-98ef-c79fcd1ced90@yandex-team.ru> (raw)
In-Reply-To: <7c1cef87-2940-eb17-51d4-cbc40218b770@redhat.com>
On 08/05/2020 17.49, Waiman Long wrote:
> On 5/8/20 8:23 AM, Konstantin Khlebnikov wrote:
>> Count of buckets is required for estimating average length of hash chains.
>> Size of hash table depends on memory size and printed once at boot.
>>
>> Let's expose nr_buckets as sixth number in sysctl fs.dentry-state
>
> The hash bucket count is a constant determined at boot time. Is there a need to use up one dentry_stat entry for that? Besides one can get
> it by looking up the kernel dmesg log like:
>
> [ 0.055212] Dentry cache hash table entries: 8388608 (order: 14, 67108864 bytes)
Grepping logs since boot time is a worst API ever.
dentry-state shows count of dentries in various states.
It's very convenient to show count of buckets next to it,
because this number defines overall scale.
>
> Cheers,
> Longman
>
next prev parent reply other threads:[~2020-05-08 16:16 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-08 12:23 [PATCH RFC 0/8] dcache: increase poison resistance Konstantin Khlebnikov
2020-05-08 12:23 ` [PATCH RFC 1/8] dcache: show count of hash buckets in sysctl fs.dentry-state Konstantin Khlebnikov
2020-05-08 14:49 ` Waiman Long
2020-05-08 16:16 ` Konstantin Khlebnikov [this message]
2020-05-08 19:05 ` Waiman Long
2020-05-08 19:38 ` Konstantin Khlebnikov
2020-05-08 20:00 ` Waiman Long
2020-05-08 20:03 ` Matthew Wilcox
2020-05-08 12:23 ` [PATCH RFC 2/8] selftests: add stress testing tool for dcache Konstantin Khlebnikov
2020-05-13 1:52 ` Dave Chinner
2020-05-08 12:23 ` [PATCH RFC 3/8] dcache: sweep cached negative dentries to the end of list of siblings Konstantin Khlebnikov
2020-05-08 19:38 ` Waiman Long
2020-05-08 12:23 ` [PATCH RFC 4/8] fsnotify: stop walking child dentries if remaining tail is negative Konstantin Khlebnikov
2020-05-08 12:23 ` [PATCH RFC 5/8] dcache: add action D_WALK_SKIP_SIBLINGS to d_walk() Konstantin Khlebnikov
2020-05-08 12:23 ` [PATCH RFC 6/8] dcache: stop walking siblings if remaining dentries all negative Konstantin Khlebnikov
2020-05-08 12:23 ` [PATCH RFC 7/8] dcache: push releasing dentry lock into sweep_negative Konstantin Khlebnikov
2020-05-08 12:23 ` [PATCH RFC 8/8] dcache: prevent flooding with negative dentries Konstantin Khlebnikov
2020-05-08 14:56 ` Matthew Wilcox
2020-05-08 16:29 ` Konstantin Khlebnikov
2020-05-08 21:07 ` Waiman Long
2020-12-09 23:01 ` [PATCH RFC 0/8] dcache: increase poison resistance Junxiao Bi
2020-12-12 7:32 ` Konstantin Khlebnikov
2020-12-13 18:49 ` Junxiao Bi
2020-12-14 7:43 ` Konstantin Khlebnikov
2020-12-14 23:10 ` Junxiao Bi
2020-12-16 18:46 ` Junxiao Bi
2020-12-17 15:47 ` Konstantin Khlebnikov
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