Wednesday, June 3, 2009

New to Linux

The short version of the story is that I need a good link to a something on Linux performance tuning. Anybody who feels like dropping a link in the comments, or a book title and/or author will be much appreciated. My own reading thus far has been the first link from my google search, which is also the highest ranked in delicious.

Here's the long version for those who are interested:

So I went and downloaded Ubuntu and the installation experience was a whole lot less painful than I expected, in fact, easier than a windows install. I spent about a half an hour confirming what I had found out during a previous attempt at dual booting--that it wasn't going to partition my hard drive. I was willing to make a complete break with windows at this point. With my Compaq recover discs, it would take about a half an hour to do a wipe-clean and reinstall of windows. But then it would take a very long time to download all the updates and get everything set up right, and it would take less time than previously to again reach the point where I am now, the point where bootup times have multiplied by a factor of something obscene and the performance has gone to hell and it's time to consider re-installing windows or switching to Linux again. So I wipe the hard drive and dive fully into Ubuntu.

I don't count the half hour I spent determining that my hard drive isn't going to partition, so the Ubuntu install was about a half an hour. It found my internet connection without any input from me and I was up and running. Responsiveness all around has been a major improvement over windows.

Video, on the other hand, has been a bit wierd. Once I installed VLC, it played DVD's full screen with only a few hiccups. Windows played them without hiccups even when overall performance was in the toilet, but that's a reasonable trade-off. Now that I'm getting comfortable in linux-land, I can probably performance-tune these hiccups away. This is where it gets interesting.

I know only the little I learned in 303, and then what I've picked up doing most of my homework on lab machines when the assignment didn't require me to be on windows. So I know almost nothing.

I open up a terminal and type free:

total used free shared buffers cached
Mem: 449520 442172 7348 0 14376 183256
-/+ buffers/cache: 244540 204980
Swap: 1317288 8 1317280

What's up with this? I have 2 terminals and emacs running and it's ussing 442 of my 449 megs of RAM?

ps shows only bash running, I know that isn't the case, because I'm typing in emacs right now. I know that Ubuntu sets me up as something less than root, and that you use sudo to up your priviledges, but sudo ps gives the same result. That can't be right. I tried adjusting the kernel.threads-max on the advice of this page, the first hit on my search for "Ubuntu performance tuning". Making that smaller didn't seem to help my video playback, and actually seemed to make it a bit worse. Upping it didn't help either. This reminded me that I really don't know what I'm doing here and should do a bit more homework before I start randomly messing with things. I rebooted to get my original value back and decided to post this issue to the intertubes.