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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Thiago Rafael Becker <trbecker@gmail.com>
CC:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "tbecker@redhat.com" <tbecker@redhat.com>,
        Steve Dickson <steved@redhat.com>
Subject: Re: [RFC PATCH 0/7] Introduce nfs-readahead-udev
Thread-Topic: [RFC PATCH 0/7] Introduce nfs-readahead-udev
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Date:   Wed, 9 Mar 2022 19:33:50 +0000
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> On Mar 9, 2022, at 1:26 PM, Thiago Rafael Becker <trbecker@gmail.com> wro=
te:
>=20
> This patch series introduces nfs-readahead-udev, a utility to
> automatically set NFS readahead when a mountpoint is mounted.
>=20
> The tool currently supports setting read ahead per mountpoint, nfs major
> version, or by a global default value.

Hi Thiago --

Your cover letter explains "what", but it should also
explain "why". I don't recall seeing previous discussion
of an issue in this area, but then, my memory isn't what
it used to be. If there is a previous thread (or threads)
please provide some links to the threads on lore.kernel.org
in your cover letter.

Good "why" information includes:

Do you, for example, have some performance results that
demonstrate a problem and some improvement? Are there
one or two specific use cases for adjusting NFS readahead?
What are the requirements for doing this via udev versus
via some other mechanism?

Having that kind of information helps us review your
patches.

Also, since this is a client-side tool (IIUC) please Cc:
Trond and Anna. You don't have to Cc: me, since I'm a
Linux NFS server maintainer.

And also: I'm not sure what Red Hat's contributor
policy is, but do you need "Signed-off-by: Thiago
Rafael Becker <tbecker@redhat.com?" instead of your
gmail address? Just making sure all the legal p's
and q's are dotted and crossed.


> Thiago Rafael Becker (7):
>  Create nfs-readahead-udev
>  readahead: configure udev
>  readahead: create logging facility
>  readahead: only set readahead for nfs devices.
>  readahead: create the configuration file
>  readahead: add mountpoint and fstype options
>  readahead: documentation
>=20
> .gitignore                                    |   6 +
> configure.ac                                  |   4 +
> tools/Makefile.am                             |   2 +-
> tools/nfs-readahead-udev/99-nfs_bdi.rules.in  |   1 +
> tools/nfs-readahead-udev/Makefile.am          |  26 +++
> tools/nfs-readahead-udev/config_parser.c      |  25 +++
> tools/nfs-readahead-udev/config_parser.h      |  14 ++
> tools/nfs-readahead-udev/list.h               |  48 ++++
> tools/nfs-readahead-udev/log.h                |  16 ++
> tools/nfs-readahead-udev/main.c               | 211 ++++++++++++++++++
> .../nfs-readahead-udev/nfs-readahead-udev.man |  47 ++++
> tools/nfs-readahead-udev/parser.y             |  85 +++++++
> tools/nfs-readahead-udev/readahead.conf       |  15 ++
> tools/nfs-readahead-udev/scanner.l            |  19 ++
> tools/nfs-readahead-udev/syslog.c             |  47 ++++
> 15 files changed, 565 insertions(+), 1 deletion(-)
> create mode 100644 tools/nfs-readahead-udev/99-nfs_bdi.rules.in
> create mode 100644 tools/nfs-readahead-udev/Makefile.am
> create mode 100644 tools/nfs-readahead-udev/config_parser.c
> create mode 100644 tools/nfs-readahead-udev/config_parser.h
> create mode 100644 tools/nfs-readahead-udev/list.h
> create mode 100644 tools/nfs-readahead-udev/log.h
> create mode 100644 tools/nfs-readahead-udev/main.c
> create mode 100644 tools/nfs-readahead-udev/nfs-readahead-udev.man
> create mode 100644 tools/nfs-readahead-udev/parser.y
> create mode 100644 tools/nfs-readahead-udev/readahead.conf
> create mode 100644 tools/nfs-readahead-udev/scanner.l
> create mode 100644 tools/nfs-readahead-udev/syslog.c
>=20
> --=20
> 2.35.1
>=20

--
Chuck Lever