Date: Fri, 14 Dec 2001 00:36:54 -0800 (PST) From: Matthew Dillon <dillon@apollo.backplane.com> To: Søren Schmidt <sos@freebsd.dk> Cc: cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG Subject: Re: cvs commit: src/sys/kern subr_disklabel.c Message-ID: <200112140836.fBE8asv22625@apollo.backplane.com> References: <200112140828.fBE8SL376721@freebsd.dk>
next in thread | previous in thread | raw e-mail | index | archive | help
:It seems Kirk McKusick wrote:
:> mckusick 2001/12/13 21:50:44 PST
:>
:> Modified files:
:> sys/kern subr_disklabel.c
:> Log:
:> Add disk I/O scheduling for positively niced processes.
:> When a positively niced process requests a disk I/O, make
:> it wait for its nice value of ticks before scheduling its
:> I/O request if there are any other processes with I/O
:> requests in the disk queue. For all the gory details, see
:> the ``Running fsck in the Background'' paper in the Usenix
:> BSDCon 2002 Conference Proceedings, pages 55-64.
:
:This breaks the kernel compile:
:
:../../../kern/subr_disklabel.c: In function `bioqdisksort':
:..
This seems kind of incomplete in general, actually.
What if you have several niced processes doing disk I/O?
They'll trip over each other unnecessarily. What about
background I/O? It won't be effected at all. What
about directory operations? A niced process's blocked
I/O could screw up performance for other processes. etc.
-Matt
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200112140836.fBE8asv22625>