linux-kernel - Re: [PATCH] Fix queueing work if !bdi_cap_writeback

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Tue, 18 Sep 2012 01:55:29 +0900
From:	OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
To:	Jan Kara <jack@...e.cz>
Cc:	Fengguang Wu <fengguang.wu@...el.com>, viro@...iv.linux.org.uk,
	hch@....de, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] Fix queueing work if !bdi_cap_writeback_dirty()

Jan Kara <jack@...e.cz> writes:

>> Duplicate flusher - many FSes has own task to flush.  Odd behavior in
>> the case of partition - agree, but I'm not sure why metadata is ok, and
>> it is not odd behavior.
>   Well, because there is much more of data pages then there is metadata. So
> when you do strange things (like refuse to write / reclaim) with metadata,
> it usually ends up in the noise. But when you start doing similar things
> with data pages, people will notice.

Could you explain more. So, you are thinking we have to fix current
behavior for metadata intensive applications? And what will people
notice?

>> Sorry, I'm not sure your point in latest comment. You are just saying FS
>> must flush pages on writepages()?
>   Yes.
>
>> And if alternative plan is acceptable, maybe I will not have interest to
>> this anymore.
>   Yes, the alternative plan looks better to me. But all in all I don't want
> to stop you from your experiments :) I mostly just wanted to point out that
> disabling flusher thread for a filesystem has a complex consequences which
> IMHO bring more bad than good.

OK, thanks.
-- 
OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/