From: "Martin J. Bligh" <mbligh@aracnet.com>
To: Ross Biro <rossb@google.com>, Linux-MM@kvack.org
Subject: Re: [BUG 2.4] Buffers Span Zones
Date: Wed, 30 Apr 2003 13:24:07 -0700 [thread overview]
Message-ID: <2387750000.1051734247@flay> (raw)
In-Reply-To: <3EB0071B.2020308@google.com>
> I've found that changing PAGE_OFFSET to reduce the amount of lowmem has been a very good way to exercies the VM. I've been able to cause all sorts of interesting problems by having ~20M of lowmem and 3G of highmem. I assume that many of these problems would occur on systems with 1G of lowmem and 16-20G of highmem.
>
> Please CC me on any responses.
It does indeed fall over quite easily on larger machines. Raw IO makes
it fall over under a light breath of wind (I think it allocates 1024
buffer_heads up front).
I've seen about 400MB of buffer_heads before - sucks.
There were some discussion on the archives with Andrew around the middle
of last year - those might prove helpful. We agreed at OLS last year
to free them immediately after read, but Andrea wanted to keep them around
after write, and reclaim them lazily (I might have that switched read vs
write). That's fixed in 2.5 and 2.4-aa I think (though I haven't retested
2.4-aa with raw IO recently). None of it is merged in mailine 2.4 still,
as far as I know, so it still falls over pretty easily.
M.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"aart@kvack.org"> aart@kvack.org </a>
next prev parent reply other threads:[~2003-04-30 20:24 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-04-30 17:25 Ross Biro
2003-04-30 20:24 ` Martin J. Bligh [this message]
2003-05-01 9:45 ` Andrew Morton
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=2387750000.1051734247@flay \
--to=mbligh@aracnet.com \
--cc=Linux-MM@kvack.org \
--cc=rossb@google.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