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Date:   Fri, 25 Mar 2022 09:46:46 +0100
From:   Karel Zak <kzak@redhat.com>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     Theodore Ts'o <tytso@mit.edu>,
        Christian Brauner <brauner@kernel.org>,
        Miklos Szeredi <mszeredi@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Linux API <linux-api@vger.kernel.org>,
        linux-man <linux-man@vger.kernel.org>,
        LSM <linux-security-module@vger.kernel.org>,
        Ian Kent <raven@themaw.net>,
        David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Amir Goldstein <amir73il@gmail.com>,
        James Bottomley <James.Bottomley@hansenpartnership.com>
Subject: Re: [RFC PATCH] getvalues(2) prototype
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On Thu, Mar 24, 2022 at 09:44:38AM +0100, Miklos Szeredi wrote:
> > If so, have you benchmarked lsof using this new interface?
> 
> Not yet.  Looked yesterday at both lsof and procps source code, and
> both are pretty complex and not easy to plug in a new interface.   But
> I've not yet given up...

I can imagine something like getvalues(2) in lsblk (based on /sys) or
in lsfd (based on /proc; lsof replacement). The tools have defined set
of information to read from kernel, so gather all the requests to the
one syscall for each process or block device makes sense and it will
dramatically reduce number of open+read+close syscalls.

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com