Some Kernel and optimization related questions

ethail · 2011-04-16 17:52:41

Last monday I asked about what was the best way to compile a kernel to apply a patch ( solving an hibernation resuming problem). Using the ABS turned to be an easy solution with a shiny patched kernel that works GREAT. Yestertay, I tried e4rat in order to speed up my boot process, wich now takes 1 min or so from burg to kde4 with Chrome, Eclipse, Spideroak and Dropbox all full loaded and functional on my laptop when before using E4rat that took nearly 3-4 minutes.

Laptop specs: Fujitsu Esprimo Mobile V6535 --> Intel T4300, 4 GB 800MHz DDR2 RAM, Intel GMA 4500M, atheros wifi chipset. Non-laptop related hardware (if needed to have in mind) Microsoft Natural Ergonomic Keyboard 4000 and Lifechat LX3000 headset, Logitech G5 mouse.

Currently the laptop is my main computer and used to internet-browsing, programming and sometimes to watch movies. No games.

I really enjoyed all the tweaking involved on the last week with the kernel patching and e4rat, so I want more.

Ok then, I was going to try readahead ( https://wiki.archlinux.org/index.php/Readahead ) and then I see that on the AUR there are some packages related to it, and this is the point when the questions come:

1) The article on the wiki points out to readahead-list, but there what seems to me another implementation, readahead-fedora. To me it seems obvious that the implementation may be different, but, what are the differences betweent the two?

2) what has to do ureadahead with the two said before? Plus, what is the point with the package description? "ureadahead is used during boot to read files in advance. readahead-list and sreadahead are out-of-date. Needs patched kernel!" The last part has not problem to me as kernel26-yi 2.6.38.2-2 seems to patch the kernel to support ureadahead, but is the first sentence, the one that talks about readahead-{list,fedora} being outdated. Could someone clarify this?

3) About kernel26-yi 2.6.38.2-2. ¿Does only a kernel install or a full compilation? ¿What kind of patches does it ship with? (Aside from ureadahead support)

4) https://wiki.archlinux.org/index.php/Im … tom_Kernel . Aside from the warning about the possible trouble with modules, is there any kind of common incidence with that options? Any kind of suggestion about more config options related to performance or to have in mind?

5) Any other kind of suggestion?

Feel free to suggest any option that trades RAM for performance, currently only a third of my RAM is used (or said in other words, more than half of my RAM is being unused (therefore useless)) and only gets to half or 2/3 when virtualbox is launched (twice everyday, during 5 mins or so)

Thank you all in advance for your help.

EDIT: I forgot to say, I like KDE and changing it is not an option, but feel fre to comment options on that way if you consider it would be a big deal.

Last edited by ethail (2011-04-16 18:55:26)

demian · 2011-04-16 21:10:55

Someone correct me if I'm wrong but I think the readahead functionality was merged into the kernel quite some time ago.

One thing you can try for improved performance is the BFS scheduler oder the -CK patchset in general. I tried it once and for some activities it improved performance quite noticably.

P.S.: Tried the -fastboot kernel boot parameter yet?

Last edited by demian (2011-04-16 21:11:46)

ethail · 2011-04-16 21:29:07

Yes, I forgot to mention that, but already using fastboot parameter (if that is the fastboot on my burg linux line, then i'm using it). As said, I'm very happy with my current status about booting and performance, no complains, only that something inside me wants to keep pushing on this.

I read a bit about BFS and the CK patches today, maybe I'll give it a try, maybe not now, but someday sure.

demian wrote:

I tried it once and for some activities it improved performance quite noticably.

Did you notice some kind of performance decrease on other activities?

ethail · 2011-04-18 22:07:57

It's not my style to do double posting or bumping threads, but got some question:

I'm going to give BFS kernel a try. But also wanted to give a try to readahead (using uber-readahead, which requires a kernel patch) but I read somewhere that readahead stuff and e4rat do not play well together. Could anyone confirm this? If that's true, which one should give better results?

One last thing: Are preload and prelink incompatible with any of readahead or e4rat?

Thank you.

Arch Linux

#1 2011-04-16 17:52:41

Some Kernel and optimization related questions

#2 2011-04-16 21:10:55

Re: Some Kernel and optimization related questions

#3 2011-04-16 21:29:07

Re: Some Kernel and optimization related questions

#4 2011-04-18 22:07:57

Re: Some Kernel and optimization related questions

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