LWN.net Logo

seekwatcher v0.11

From:  Chris Mason <chris.mason@oracle.com>
To:  linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject:  [ANNOUNCE] seekwatcher v0.11
Date:  Mon, 14 Apr 2008 11:49:34 -0400
Message-ID:  <200804141149.34556.chris.mason@oracle.com>
Archive-link:  Article, Thread

Hello everyone,

seekwatcher uses blktrace data to create IO graphs and movies.  I mainly use 
it to compare and tune filesystems under different workloads.

The main update in v0.11 is the ability to run blktrace for multiple block 
devices.  I'm using this for the btrfs multi-device code, but it can also 
help figure out what lvm/md are doing to the underling block devices.

Example:

seekwatcher -t dd.trace -d /dev/sda1 -d /dev/sdb1 -o dd.png \
	-p 'dd if=/dev/zero of=/mnt/file bs=1M count=4000'

Leads to something like this (the png below was 4 devices):

http://oss.oracle.com/~mason/seekwatcher/btrfs-raid0.png

It does a simple concatenation of the block numbers it finds in the blktrace 
output, and sorts the traces from all the devices by time.

Other examples and download information are available here:

http://oss.oracle.com/~mason/seekwatcher/

-chris

Copyright © 2008, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds