Subject: kern/8885: raidctl -i being excessively slow
To: None <gnats-bugs@gnats.netbsd.org>
From: None <nemo@red-bean.com>
List: netbsd-bugs
Date: 11/26/1999 13:03:47
>Number:         8885
>Category:       kern
>Synopsis:       raidctl -i is being excessively slow
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 26 13:03:01 1999
>Last-Modified:
>Originator:     Joel N. Weber II
>Organization:
Red Bean Software/Gratuitous Organization for Gratuitous Software Enhancement
>Release:        
>Environment:
Note: this is actually a kernel from the 1.4 branch from cvs from last weekend.
System: NetBSD duality 1.4.1 NetBSD 1.4.1 (XANTHINE) #0: Thu Nov 25 14:00:04 EST 1999 nemo@duality:/usr/src/syssrc/sys/arch/i386/compile/XANTHINE i386


>Description:
`systat iostat' is telling me that the average amount of disk activity is
about 100 kilobytes per second, while I'm doing raidctl -i on a 10GB partition.
Given that I believe the disks I'm using are capable of something on the order
of 2 megabytes per second, this seems unacceptably slow.  I suspect there's
something in the raid code which makes it much less agressive than it should
be.

It appears to be the case that raidctl -i starts out running reasonably fast,
and then is slow for most of the rest of the process, but I haven't yet studied
this in great detail.

If it's relavent, the fifo queue size I set in the raid configuration file
is 100.
>How-To-Repeat:
>Fix:
>Audit-Trail:
>Unformatted: