Block IO Tracing
----------------
-Written by Jens Axboe <axboe@suse.de> (initial version and kernel support),
+Written by Jens Axboe <axboe@kernel.dk> (initial version and kernel support),
Alan D. Brunelle (threading and splitup into two seperate programs),
Nathan Scott <nathans@sgi.com> (bug fixes, process names, multiple devices)
Also thanks to Tom Zanussi <zanussi@us.ibm.com> for good input and
Requirements
------------
-You need to be running a 2.6.14-rc3 kernel or newer, with the blk-trace patch
-included in this repository. If you forgot where you got it, the url is:
+blktrace was integrated into the mainline kernel between 2.6.16 and 2.6.17-rc1.
+The target trace needs to run on a kernel at least that new.
-rsync://rsync.kernel.org/pub/scm/linux/kernel/git/axboe/blktrace.git
+git://git.kernel.dk/blktrace.git
If you don't have git, you can get hourly snapshots from:
-http://www.kernel.org/pub/linux/kernel/people/axboe/blktrace/
+http://brick.kernel.dk/snaps/
The snapshots include the full git object database as well. kernel.org has
excessively long mirror times, so if you have git installed, you can pull
the master tree from:
-git://brick.kernel.dk/data/git/blktrace.git
+git://git.kernel.dk/blktrace.git
For browsing the repo over http and viewing history etc, you can direct
your browser to:
-http://brick.kernel.dk/git
+http://git.kernel.dk/
Usage
-----
-$ blktrace -d <dev> [ -r relay_path ] [ -o output ] [ -k ] [ -w time ]
+$ blktrace -d <dev> [ -r debug_path ] [ -o output ] [ -k ] [ -w time ]
[ -a action ] [ -A action mask ]
-d Use specified device. May also be given last after options.
- -r Path to mounted relayfs, defaults to /relay.
+ -r Path to mounted debugfs, defaults to /sys/kernel/debug.
-o File(s) to send output to.
-D Directory to prepend to output file names.
-k Kill running trace.
-l Run in network listen mode (blktrace server)
-h Run in network client mode, connecting to the given host
-p Network port to use (default 8462)
- -s Make the network client use sendfile() to transfer data
+ -s Disable network client use of sendfile() to transfer data
-V Print program version info.
$ blkparse -i <input> [ -o <output> ] [ -b rb_batch ] [ -s ] [ -t ] [ -q ]
%a - Action
%c - CPU ID
- %C - Task command name
+ %C - Task command (process) name
%d - Direction (r/w)
%D - Device number
%e - Error number
-F Format specification. The individual specifiers are:
A - Remap
- B - Back merge
+ B - Bounce
C - Complete
D - Issue
+ M - Back merge
F - Front merge
G - Get request
I - Insert
- M - Both front and back merge
P - Plug
Q - Queue
R - Requeue
-20051007, Jens Axboe <axboe@suse.de>
+2006-09-05, Jens Axboe <axboe@kernel.dk>