linux-raid.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: NeilBrown <neilb@suse.de>
To: Shaohua Li <shli@fb.com>
Cc: linux-raid@vger.kernel.org, Kernel-team@fb.com,
	songliubraving@fb.com, hch@infradead.org,
	dan.j.williams@intel.com
Subject: Re: [PATCH v2 0/6] a caching layer for raid5/6
Date: Wed, 20 May 2015 15:23:53 +1000	[thread overview]
Message-ID: <20150520152353.175365f4@notabene.brown> (raw)
In-Reply-To: <cover.1432003804.git.shli@fb.com>

[-- Attachment #1: Type: text/plain, Size: 2033 bytes --]


hi,
 I cannot possible give any consideration to this caching layer until I'm
 happy with the code I got from you for stripe batching, and I'm not.

I asked:

Subject: Re: [PATCH 7/7] md/raid5: fix handling of degraded stripes in batches.
Date: Wed, 13 May 2015 10:56:04 +1000

> What exactly do you expect to happen after the stripes in a batch after they
> have been split up?

and haven't received a reply yet.
Did you not get that email?

Thanks,
NeilBrown



On Mon, 18 May 2015 19:57:28 -0700 Shaohua Li <shli@fb.com> wrote:

> Hi,
> 
> This is the second version of the raid5/6 caching layer patches. The patches add a
> caching layer for raid5/6. The caching layer uses a SSD as a cache for a raid
> 5/6. It works like the similar way of a hardware raid controller. The purpose
> is to improve raid performance (reduce read-modify-write) and fix write hole
> issue. The main patch is patch 3 and the description has all details about the
> implementation.
> 
> Main changes of V2 are to improve performance. Meta data write doesn't use FUA
> any more. Discard request is only dispatched when discard range is big enough.
> Also have some bug fixing and code cleanup. Please review!
> 
> Thanks,
> Shaohua
> 
> 
> Shaohua Li (5):
>   raid5: directly use mddev->queue
>   raid5: A caching layer for RAID5/6
>   raid5: add some sysfs entries
>   md: don't allow resize/reshape with cache support
>   raid5: skip resync if caching is enabled
> 
> Song Liu (1):
>   MD: add a new disk role to present cache device
> 
>  drivers/md/Makefile            |    2 +-
>  drivers/md/md.c                |   14 +-
>  drivers/md/md.h                |    4 +
>  drivers/md/raid5-cache.c       | 3519 ++++++++++++++++++++++++++++++++++++++++
>  drivers/md/raid5.c             |   97 +-
>  drivers/md/raid5.h             |   16 +-
>  include/uapi/linux/raid/md_p.h |   73 +
>  7 files changed, 3705 insertions(+), 20 deletions(-)
>  create mode 100644 drivers/md/raid5-cache.c
> 


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 811 bytes --]

      parent reply	other threads:[~2015-05-20  5:23 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-19  2:57 [PATCH v2 0/6] a caching layer for raid5/6 Shaohua Li
2015-05-19  2:57 ` [PATCH v2 1/6] MD: add a new disk role to present cache device Shaohua Li
2015-05-19  2:57 ` [PATCH v2 2/6] raid5: directly use mddev->queue Shaohua Li
2015-05-19  2:57 ` [PATCH v2 4/6] raid5: add some sysfs entries Shaohua Li
2015-05-19  2:57 ` [PATCH v2 5/6] md: don't allow resize/reshape with cache support Shaohua Li
2015-05-19  2:57 ` [PATCH v2 6/6] raid5: skip resync if caching is enabled Shaohua Li
2015-05-19  9:22 ` [PATCH v2 0/6] a caching layer for raid5/6 Artur Paszkiewicz
2015-05-20  5:23 ` NeilBrown [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20150520152353.175365f4@notabene.brown \
    --to=neilb@suse.de \
    --cc=Kernel-team@fb.com \
    --cc=dan.j.williams@intel.com \
    --cc=hch@infradead.org \
    --cc=linux-raid@vger.kernel.org \
    --cc=shli@fb.com \
    --cc=songliubraving@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).