maemo.org - Talk - BFS for the power kernel

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- Maemo 5 / Fremantle (https://talk.maemo.org/forumdisplay.php?f=40)

- - BFS for the power kernel (https://talk.maemo.org/showthread.php?t=58780)

Re: BFS for the power kernel

I have noticed that Opera is heavily influenced by BFS kernel. There is a lot of flickering and UI flashes and it looks buggy as hell. As I use Opera alot and this renders using this browser not very pleasant experience I will switch back to power kernel. This is propably due to bad coding in Opera exposed by BFS. Other software does not seem to be influenced at all.

Re: BFS for the power kernel

Quote:

Originally Posted by DrWilken (Post 768129)

Wonder why they didn't use the noop scheduler by default.

Just noticed the SIO scheduler which is included in pf-kernel:

Code:

The Simple I/O scheduler is an extremely simple scheduler,

based on noop and deadline, that relies on deadlines to

ensure fairness. The algorithm does not do any sorting but

basic merging, trying to keep a minimum overhead. It is aimed

mainly for aleatory access devices (eg: flash devices).

Re: BFS for the power kernel

Quote:

Originally Posted by jehan (Post 770091)

Just noticed the SIO scheduler which is included in pf-kernel:

Code:

The Simple I/O scheduler is an extremely simple scheduler,

based on noop and deadline, that relies on deadlines to

ensure fairness. The algorithm does not do any sorting but

basic merging, trying to keep a minimum overhead. It is aimed

mainly for aleatory access devices (eg: flash devices).

Never heard about SIO... ;) Thanks... :)

Re: BFS for the power kernel

This article mentions some new patches aimed at improving desktop responsiveness: http://www.phoronix.com/scan.php?pag...item&px=ODQ3Mw

I have been super busy lately with other projects but I will try back porting these patches in the next few days.

Re: BFS for the power kernel

Quote:

Originally Posted by coreyoconnor (Post 775538)

Sounds great! Looking forward to seeing BFS and/or CFQ scheduler fixes for Maemo 5.

Re: BFS for the power kernel

Quote:

Originally Posted by coreyoconnor (Post 775538)

Have you had any luck back porting those patches? They sure look like a worthy addon for the N900 :)

Also, I'm sure you've came across this post too:

Quote:

Originally Posted by Phoronix

Nokia has funded some development work that has resulted in a set of eleven patches for exposing CFS low-latency features.

-Source: http://www.phoronix.com/scan.php?pag...item&px=ODU0OQ

Just a heads-up, not a request ;)

One more question btw: which version of BFS have you incorporated in the kernel-power?
And if possible and time permits, could you try compiling the latest BFS patch with the (if possible, newest) kernel-power?

Keep up the good work, I really like this thread.

-iDont

Re: BFS for the power kernel

Quote:

Originally Posted by iDont (Post 800023)

Have you had any luck back porting those patches? They sure look like a worthy addon for the N900 :)

Also, I'm sure you've came across this post too:

-Source: http://www.phoronix.com/scan.php?pag...item&px=ODU0OQ

Just a heads-up, not a request ;)

I have a test patch for the VM under IO pressure provided here:
http://lkml.org/lkml/2010/8/1/40

However the 2.6.34+ vmscan.c has changed significantly from the 2.6.28 vmscan.c. I think I messed up somewhere cause my patch causes the device to stick in lumpy reclaim mode continuously. Basically makes it unusable as soon as any VM scan operation occurs.

I have been travelling and haven't had a chance to work on any of the newer patches either. but I plan to!

Quote:

Originally Posted by iDont (Post 800023)

One more question btw: which version of BFS have you incorporated in the kernel-power?
And if possible and time permits, could you try compiling the latest BFS patch with the (if possible, newest) kernel-power?

Keep up the good work, I really like this thread.

-iDont

I specifically started with the BFS 316 patch for 2.6.27 here:
http://ck.kolivas.org/patches/bfs/Un...C-2.6.27.patch

Although it contains a few bits and pieces from the 2.6.31 BFS 316 patch - Just because some of the 2.6.27 patch does not apply to 2.6.28.

Course, now that I check I find that BFS is now up to 330.. HMM! Looks like an update is in order.

My code is a proper branch of the kernel-power git tree. First on my list is to make a garage page for this branch.

Re: BFS for the power kernel

I have no plans to enable BFS in the official kernel-power package as BFS seems to be to unstable and cannot be disabled during runtime.
You could, however, join the kernel-power project and create a git branch for your patches.

Quote:

Originally Posted by coreyoconnor (Post 801798)

My code is a proper branch of the kernel-power git tree. First on my list is to make a garage page for this branch.

Re: BFS for the power kernel

Quote:

Originally Posted by titan (Post 802012)

You could, however, join the kernel-power project and create a git branch for your patches.

I will keep it a separate project. I already create a git branch for these patches.

Re: BFS for the power kernel

Quote:

Originally Posted by coreyoconnor (Post 801798)

Take your time, travelling is great. The fact that somebody is looking into the patches is already good news on its own :)

Quote:

Originally Posted by coreyoconnor (Post 801798)

Thank you for your time and work on this. I've been using BFS on my single core machines for a while now and, in my opinion, it's also a great addition to the N900. I'm looking forward to see a garage page pop up!

Quote:

Originally Posted by coreyoconnor (Post 802285)

I will keep it a separate project. I already create a git branch for these patches.

FYI, I emailed Titan about this thread. That's probably the reason for his reply in this thread.

Again, keep up the good work, both you and Titan!

-iDont