Last 5 Posts from 2006/May

Today I've released a new version of Eagle (download versions for desktop or maemo), this new version features a Rich Text widget, bug fixes and minor improvements.

Also starring today is Maemo Task Manager, the first Eagle-Maemo application to be released.

Both Eagle and Task Manager are sponsored by my employer INdT.

Please notice these screenshots are from scratchbox environment, that's why you see kde processes there!

As you might know, I'm always looking for ways to speed up my system boot.

Today I discovered fcache. It was created by Jex Axboe, from CFQ io-elevator fame, and was announced at LKML on 2006-05-15. He aims to reduce bootup times by speeding up access to files and does this laying out data linearly on disc. It happens in an extra partition that will hold cache data, this cache will be written by fcache while in "priming" mode: every read from cached partition will be appended to cache. While in "normal" operation mode, it will lookup data from cache instead of real file system.

This makes a solution even better than the one I envisioned before, that was automatic on-line defragmentation. It's simpler, more efficient and works for every file systems!

Thank you, Jens!

Today I read an entry at planet.maemo from Teemu about GTalk (VoIP), it was So it is Google Talk then….

While I agree with some points, I have some to add:

• 770 is spread as a internet device, then makes sense to pair with some big internet service provider. And Google is a big one. I can envision Google's applications like Calendar and possible other Internet-PIM to work flawlessly on 770 opera browser. It would be a great step, since device lacks a pre-installed PIM application.
• Why wait for Telepathy? Why not try Tapioca-VoIP? It runs on your desktop today and will run on 770 as soon as we have the new software, with GStreamer 0.10. Also, Tapioca-VoIP provides Python API!

About Python comments, I really hope it will improve, I know some PyMaemo guys and they're working hard to fix problems found in current version. Meanwhile, I'm working on Eagle to make easier for us developers to have GUI for our applications on 770.

Last, but not least, My presentation at GUADEC will cover all these topics: I will demonstrate Python on Maemo by coding an Eagle application that uses Tapioca :-)

Today Eero Tamminen suggested at maemo-developers a good read: http://people.redhat.com/drepper/dsohowto.pdf

It explains how shared libraries works and possible optimizations on its usage, a must read for us developers.

I'm still reading, but seems really useful.

Yesterday I got my Kubuntu machine updated, it's a bit faster now, but still not as fast as I would like.

So I went to try to speed things up. Given I did not install it myself, I don't know if he did most procedures I do and I noticed the guy didn't. Some things I did:

File System Speedups: since I use a laptop (slow disks) with dm-crypt, making filesystem as fast as possible is crucial. Also, avoid forced fsck since it may show while booting for a talk/presentation (as it already did!) and avoid huge reserved space for super user, since HD is not that big. Changes:

• Save previous ext3 state: dumpe2fs $EXT3_PARTITION > ext3-state.txt
• Turn off forced fsck runs: tune2fs -i0 $EXT3_PARTITION
• Turn on dir_index on ext3, for faster searchs and file lookup: tune2fs -O dir_index,sparse_super,has_journal,filetype $EXT3_PARTITION
• (Possibly) reduce amount of reserved space for super user. It defaults to 5%, but maybe it's too much for you, or it's not needed (if you use /home partition) calculate amount with AMOUNT=512*100/$FS_SIZE_IN_MB to reserve 512mb. Set it with tune2fs -m$AMOUNT $EXT3_PARTITION; tune2fs -m0 $HOME_EXT3_PARTITION
• Have ext3 to rebuild indexes and thus use dir_index (first unmount partitions, you may boot from a livecd): fsck.ext3 -fCD $EXT3_PARTITION
• User greater ext3 commit interval. It defaults to 5 seconds, but on laptops with good battery you can make it 15-60. I use 15 (home) and 60 (system, also with noatime) for fail-safety: edit /etc/fstab and append commit=15 to filesystem options.

Hardware Settings: it's all about hdparm. Edit /etc/hdparm.conf and make sure, at least dma=on and interrupt_unmask=on are set.

Network: If you often change networked and non-networked environments, you may notice boot can take a lot if you have interfaces as "auto" in /etc/network/interfaces. Remove them all from auto and install ifplugd, it will then detect if network is physically available and if so launch them. You may also install and configure wpasupplicant in order to automatically change among WEP, WPA and WPA2 wireless networks, but be aware to set wpa-conf /etc/wpa_supplicant.conf in interface option in /etc/network/interfaces

X.org: use 16 instead of 24 bits-per-pixel, at least it will consume less memory.

Kernel: use latest Con Kolivas' kernel patch. It makes desktop more responsive.

Services: disable unused services in /etc/rcS.d and /etc/rc2.d. I do not use PCMCIA, PPP, EVMS, NFS and a bunch of other services. Also, readahead seems to be optimized to GNOME rather KDE, so I disabled it too (readahead-desktop).

My system (IBM ThinkPad T41, 512mb of RAM, 40Gb Fujitsu MHT2040HA, 1.6Ghz/1MB cache Pentium-M) boots to KDM in 45s, remember that I use dm-crypt! It's still far from how many seconds I think it should take, but things are still improving in GNU/Linux.