I have recently installed MDK 10.1 CE and am pretty pleased with it. One of the minor annoyances I have with it is that SOMETHING is writing to the hard disk every 5 seconds or so. If I simply watch the system, doing nothing with it, I can see and hear the disk be accessed about every 5 seconds. Since I can see the disk access light go on, clearly something is writing to the disk about every 5 seconds. Does anyone have any idea of what this might be, or how I might track it down? I have tried running "top" and watching, but there is no obvious correlation. Are there any tools that would let me get a record of each proces that accesses the disk? Thanks in advance for any pointers!

Hi.

It's the kernel. I'm not too sure about the details, but I believe it has to do with flushing dirty blocks.

There is a script in your kernel sources which switches on a thing called 'laptopmode'. This stops the disk accesses, allowing laptop drives to spin down for extended times to save power.

If you have your kernel sources installed, have a look at
<source directory>/Documentation/laptop-mode.txt

Dave

Great - thanks for the info! Now for the tough part. How do I enable lap-top mode? Your pointer to kernel-sources (I do have the package installed, needed it to build the latest Philips Webcam Driver from Saillard) suggests a kernel build. I hope perhaps there is a config file somewhere that can be changed instead?

If I have to rebuild a kernel to do this (shudder - last time I tried that I reduced my system to an inanimate hunk of hardware) that's a problem. Is there any way to enable lap-top mode without a kernel rebuild?

Alternately, is there any way to slow down the page flush cycle so that it does it less often? That could work too. Thanks!

BTW, as a relative newbie to these forums, what is affero? I see it in your address block, ilikejam. Is this a way of formally recognizing your excellent help? Thanks!

Hi.

You don't have to rebuild your kernel.
If you look in <source directory>/Documentation/laptop-mode.txt there's a section that starts with:
--------------------CONTROL SCRIPT BEGIN----------------------------------------
and ends with
--------------------CONTROL SCRIPT END------------------------------------------

Copy everything between those lines into a plain text file and call it something sensible (I called it laptopmode), then do 'chmod +x <name of text file>'

Run the newly created script with './<name of file> start' to enable, and do '<name of file> stop' to disable. (You'll have to be root to do this).

Just out of interest, is the drive accesses causing you any problem, or is it just an annoyance? Switching to laptop-mode makes it more likely that you'll lose data should your machine crash.

The affero thing's a sort of donation system, but you don't have to donate anything (you can just leave comments). Their website's a bit of a mess, so I'm not entirely sure what all the options are.

Dave

Hi, thanks for the pointer to the script for laptop mode. I will give this a whirl.

To answer your question, the disk access thing is just an annoyance, not a problem. I have a "silent PC" - I specifically ordered a custom machine from a company that specifies in silent PCs - this thing is so quiet that you almost have to be right beside the case to even know it is running. So, this 5 sec disk access stands out like sore thumb, since it is really the only sound you hear from the PC. Every 5 sec you hear the disk roll. Given the specific desire to have a quiet PC, which had been realized under the dreaded Windows, this is quite annoying. Also, I have tried out a few other distros, and MDK is the only one that seems to do this. Of course, MDK is the one I want to keep. After playing with a few others (notably FC3), I am REALLY impressed with MDK. So, I am digging in and trying to resolve the remaining issues.

By the way, if you are interested in a TRULY silent PC, I would highly recommend that you visit www.endpcnoise.com. This is where I had mine built. Just for the record, I have no commercial affiliation with these guys, I am just a VERY satisfied customer. They will get all my PC business going forward. They are located on the west coast of the United States. You deal with them via web and email and they ship your custom PC to you. They have some standard configurations which can order, or you can specify a custom configuration, which I did, and they will build it for you. No matter what, they specialize in nearly completely silent PCs. You would not believe what a relief it is to be free of the noise the average PC makes! OK, end of commercial!! :-)