All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jens Axboe <axboe@kernel.dk>
To: Milan Broz <mbroz@redhat.com>
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH] fix creating zero sized bio mempools in low memory system
Date: Mon, 4 Sep 2006 14:43:35 +0200	[thread overview]
Message-ID: <20060904124335.GM25434@kernel.dk> (raw)
In-Reply-To: <44FC1C90.200@redhat.com>

On Mon, Sep 04 2006, Milan Broz wrote:
> In the very low memory systems is in the init_bio call
> scale parameter set to zero and it leads to creating
> zero sized mempool.
> 
> This patch prevents pool_entries parameter become zero,
> so the created pool have at least 1 entry.
> 
> Mempool with 0 entries lead to incorrect behaviour 
> of mempool_free. (Alloc requests are not waken up
> and system stalls in mempool_alloc->ioschedule). 

Good catch, queued. Maybe this is the only such scaling problem,
otherwise it may be a good idea to add a WARN_ON(!min_nr) to the mempool
setup in mm/mempool.c to catch such errors.

-- 
Jens Axboe


      reply	other threads:[~2006-09-04 12:40 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-09-04 12:31 [PATCH] fix creating zero sized bio mempools in low memory system Milan Broz
2006-09-04 12:43 ` Jens Axboe [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=20060904124335.GM25434@kernel.dk \
    --to=axboe@kernel.dk \
    --cc=akpm@osdl.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mbroz@redhat.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.