04/11/2003

Disk performance XFce4 panel plugin (DiskPerf)
==============================================


1 -	Description
	-----------
The DiskPerf plugin displays disk/partition performance based on data provided by Linux kernels 2.6 or recent 2.4's (at least 2.4.20 compiled with CONFIG_BLK_STATS turned on, or possibly older kernel patched with "Disk extended statistics" in /proc/partitions),or with NetBSD, based on the dk_rbytes and db_wbytes values provided by the hw.diskstats sysctl (see iostat for details).

To know if your Linux kernel 2.4 provides such statistics:
        - less /proc/partitions
        - check that there are rsect/wsect data
2.6 kernels should always provide those statistics.

The code of this plugin has been written starting from the Xfce4 sample-plugin example (www.xfce.org), then looking at both systemload (Riccardo Persichetti - ricpersi@libero.it) and netload (Bernhard Walle - bernhard.walle@gmx.de) XFce4 goodies.
The port onto NetBSD has been made by Benedikt Meurer - benedikt.meurer@unix-ag.uni-siegen.de

DiskPerf has been intensively tested on Mandrake 9.1 (Linux kernel 2.4.21), 9.2 (2.4.22) and NetBSD 1.6W and 1.6ZE.


2 -	Installation
	------------
Do the usual stuff:
	- gunzip
        - tar xf
        - configure --prefix=<XFce4InstallationDir>	(e.g. /usr)
        - make
        - make install  (as root)
	
You should then end up with:
        libdiskperf.a   libdiskperf.la  libdiskperf.so
installed in <XFce4InstallationDir>/lib/xfce4/panel-plugins/


3 -	Port
	----
Currently, DiskPerf runs only on recent Linux kernels (2.4.20+, 2.6.x), NetBSD and OpenBSD.
If one would like to port this plugin onto another OS, please feel free to send me your patch.
Furthermore, if you wish to take over the development of DiskPerf, just let me know. I would probably be able to provide you with useful information on how to get disk statistics on some commercial Unices (e.g. SunOS/Solaris).
Adding support for other BSDs should be trivial now that we have NetBSD support, just go and watch out for the hw.diskstats sysctl.


4 -	Bugs
	----
If you find a bug (on Linux), please send me the result of "uname -a" as well as 2 snapshots of your /proc/partitions (or /proc/diskstats if kernel 2.6) taken at 10-second interval.


Enjoy!
Roger Seguin
roger_seguin@msn.com
