What do you do when your computer reacts sluggishly to even the simplest commands? You probably look at its hard disk LED to determine if the disk is busy, because if it is, the only thing that really helps is waiting (apart from buying a faster disk or SSD). Problem solved – if you are sitting right next to the machine. But what if you are using a protocol like RDP or ICA to connect to a remote computer or VM? No HDD LED, no quick and simple way to check for hard drive activity. This has been bugging me enough to write a software replacement: DiskLED.
DiskLED is a little application that sits in the system tray and flickers whenever the hard disk is accessed. It looks like this:
That could be all there is to say, but I decided to make the tool a little more flexible.
Flexibility
DiskLED queries performance counters for disk activity data. Basically, what it does is periodically query a specific counter and display the current value graphically. The cool thing is it is not limited to hard disk activity data. Using a simple INI file, DiskLED can be configured to display any counter’s data.
Obviously an LED type display is well-suited for activity data only. When dealing with many other counters, a different visualization method is needed. Here you go: DiskLED has a second display mode, similar to how Task Manager shows CPU utilization. It can be used to display the disk queue length, for example, and looks like this:
When dealing with remoting protocols like RDP or ICA one generally tries to reduce screen updates to a minimum. For that reason the frequency with which DiskLED updates its icon can be configured freely.
Usage
DiskLED comes as a standalone EXE file. No need to install anything. If you run the executable all by itself, it uses the following built-in parameters:
- Display mode: flickering LED (first example shown above)
- Performance counter used as data source (localized!): \PhysicalDisk(_Total)\% Disk Time
- Update interval: 30 ms
So if you have an English version of Windows and just need a HDD activity LED, there is nothing you need to do except run DiskLED.
Configuration
If there is anything you want to modify, create a text file, name it DiskLED.ini and put it in the same folder as the executable. A sample INI file is included in the download. Here are two different configurations for reference purposes:
Default configuration, but for a German system:
; Configuration file for DiskLED by Helge Klein
;
; http://blogs.sepago.de/helge/
;
[Performance Counter 1]
; The type of LED indicator to show
LEDType=Flicker
; The localized (!) path to the performance counter used as a data source for the LED
Path=\Physikalischer Datenträger(_Total)\Zeit (%)
; The update interval of this counter in ms
UpdateInterval=30
The second sample configuration uses a bar-style display mode to display the disk queue length (\PhysicalDisk(_Total)\Current Disk Queue Length). It updates every 500 ms only. With this display mode, you have to tell DiskLED which numerical value corresponds to 100% utilization. In the case of disk queue length, this is typically 2 on single-disk systems:
; Configuration file for DiskLED by Helge Klein
;
; http://blogs.sepago.de/helge/
;
[Performance Counter 1]
; The type of LED indicator to show
LEDType=ColoredBar
; The localized (!) path to the performance counter used as a data source for the LED
Path=Path=\PhysicalDisk(_Total)\Current Disk Queue Length
; The update interval of this counter in ms
UpdateInterval=500
; This value is considered as 100% utilization
100% Utilization=2
Download
Download DiskLED here.
Once you have tried it out, let me know what you think of DiskLED and how it can be improved by commenting on this article.
Thanks for sharing!
Hello!
I just need some explanations about that:
; The localized (!) path to the performance counter used as a data source for the LED
Path=Path=\PhysicalDisk(_Total)\Current Disk Queue Length
I just wonder how to find the name of that “performance counter” for other countries than UK/US and Germany, e.g. for France?
Also, will it work flawlessly under Windows 7 x64?
Thanks in advance,
Esteban
Esteban,
the current version 1.1 of DiskLED comes with a GUI that makes it easy to configure the path to the performance counter. Just right-click no the icon.
And yes, DiskLED runs on Windows 7 x64 – I am using it on that platform myself.
Thank you, thank you, thank you. My Dell Studio notebook has no LEDs at all, so even when I’m sitting in front of the machine I can’t tell if the hard drive is active or not. Perhaps this is a cost-cutting trend for the future. Like you I’m using DiskLED on 64 bit Windows 7, and it works perfectly.
DiskLED did not come back after reboot.
I was thrilled with DiskLED.
I put it in my startup and after rebooting, got this error message:
———————————————————–
DiskLED
InitPDH: PdhAddCounter failed with: 0xc0000bb8
This probably means that the performance counter path is invalid.
Please take note that it must be localized. The default path used (if no config file
is specified) is valid on English systems only.
OK
———————————————————–
I figured that since I changed the “Icon type” from “green bar” to “yellow/red percentage” and updated the INI file when I saved it that I must have changed more than just that.
I now get a red exclamation mark in my taskbar.
Since I actually ran this on two systems I looked at what was different. On the one that doesn’t work anymore, the three pulldown menus at the top of the config screen are blank. When I try to select PhysicalSisk or LogicalDisk in the topmost Object pulldown they aren’t there anymore.
I was able to change Object to Processor and set it to %Idle Time so it functions like the inverse of the Task Manager CPU usage and then saved this via the INI, but the PhysicalDisk and LogicalDisk options are gone.
I’m on an English system in the USA.
Any suggestions?
Bartok,
Do you see all performance objects except physical and logical disk? In that case maybe some application disabled those two. This is very easy, e.g. on the command line with “diskperf -N”.
What happens if you issue “diskperf -Y” and then reboot? That should re-enable the disk performance counters (unless some app actively re-disables them periodically).
Please let me know if that does not help.