Blog of Sylvain Le Gall

This morning, Alan sends me the link to the subscription form. We are now ready to accept participants for OCaml Meeting 2009.

Last week, I was at the annual CAML consortium meeting. We talked about OCaml Meeting with M. Leroy and other participants. Most of us, think this meeting is a real great way to make OCaml user meet. This can be the start of great projects, just because people realized that a real OCaml community exists. The INRIA seems really enthusiast about the meeting, maybe INRIA team will be directly involved in the organization in 2010.

I hope 2009 meeting will be as good as the former. At least this year, we are doing things quite in advance and the whole organization will be a little bit more "professional".

OCaml Meeting webpage

Since September 2008, Alan Schmitt and I have decided to organize a new OCaml Meeting following the JFLA. This will be the second time of such an event. Last year we were 50 people -- after a very short period for organizing it (less than a month). This year we decided to prepare things earlier.

As a matter of fact, the last year events has at least generated a peak in OCaml mailing list (602 message in January, 487 in february...) It also has given birth to several things like planet and forge. It has also help to start things like batteries. I hope this year events will help people to meet and exchange great ideas for OCaml promotion.

Waiting to see a lot of "OCaml"ers at OCaml Meeting 2009.

After three years, a new version of ocaml-gettext is out. I know that the delay is quite long... Been too busy to do anything regarding this.

This new version is mainly a bug fix release:

• UTF-8 is better handled when merging PO/POT
• multi-lines, special and continuation comments of PO file are supported
• camomile implementation is now safer (less chance to fail if something goes wrong)
• improve overall build system

However, the major event of this release is the fact that it is now compatible with OCaml 3.10.0. This is a big news, because string extraction heavily rely on camlp4, which has changed a lot.

I have also uploaded a debian package of ocaml-gettext.

Plans for next release:

• website has not been updated because generating it is too much complicated, i should switch to something more simple layout and generation scheme
• my home-made build system is not good at all (fail to detect changes and do incremental rebuild...), next release should move to ocamlbuild
• PDF generation has been disabled, because it makes fop produce a lot of errorrs, it should be re-enable
• finish the patch to xgettext to allow OCaml string been extracted

Homepage Download

Even if i don't like talking about this in public, Lucas Nussbaum blog entry decides me to write this, because I, too, agree that the Debian accounts and keyring situation is severely hurting Debian, and that a solution needs to be found RSN.

I wish to be more clear on some of my positions concerning this. First of all, I am actually being hit by a "GPG key expired" status that prevents me to vote and upload packages. It is a little bit my fault because 1) i set an expiration date on my GPG and 2) i only update this expiration date in keyring.debian.org less than 1 month before it expires -- but it was more than 3 months ago... I have pinged different people since then to get the keyring updated without success. I have reuploaded my key without expiration date, and now i know that things can take a long time inside Debian (2nd rank after waiting for my own Debian account creation).

Another point is concerning DM (Debian Maintainer). I was against the proposal when it was voted, because i was thinking it will create a "sub" status of Debian Developper (i.e people which are in between debian users and debian developers). I have changed my mind concerning this point the DM process is lightweight and everything seems to be faster with it. This is a really good points for DM (and jetring). I am also considering to sponsor myself to apply to DM, in order to have a non-expired GPG key somewhere.

Last but not least, i met several French NM at DebConf 7 (Kibi, Goneri...). At that time, i didn't know them. Since DC7, I have seen them working on different parts of Debian. I think it is a shame to make them wait so long. It is really the best way to make their motivations disappear. Looking back at my own situation, i realize that i was more active before my account creation. This is probably because it takes a long time to process, and i loose hope in a possible account creation. I am now more active in Debian, but still not doing as much as i want to.

I don't know the best solution to solve this problem. I tend to think that some key people should delegate their work to other DD (within a team ?). Last year at DC7, Sam Hocevar was already discussing this problem with the people involved in Account Creation. I don't know what was the result of this discussion...

Hope, this post will help to show that this problem is important.

I just installed a new kernel on my thinkpad. The migration was done from a 2.6.23 kernel and brings a new 80211g driver: iwl3945.

This new driver is fully included in the kernel and only need an additional firmware, which can be found in firmware-iwlwifi Debian package. It works pretty well, seems to connect faster, but the blinking WIFI antenna on my laptop doesn't work anymore. It replaces ipw3945 with a daemon in user space.

The installation was not straightforward, since ipw3945 and udev persistent net rules prevent it. The solution is to remove lines concerning the net interface using ipw3945 (the line "# PCI device 0x8086:0x4227 (ipw3945)" and the line after) in the file /etc/udev/rules.d/z25_persistent-net.rules. After this, you must do:

modprobe -r iwl3945
modprobe iwl3945

The file /etc/udev/rules.d/z25_persistent-net.rules now contains a line for the iwl3945 driver.

Installing the driver for etch requires to update the package wireless-tools using its backport to etch and downloading/installing the package firmware-iwlwifi from unstable.

I have spent one day and a half this week-end at FOSDEM. This was not as great as expected, but mostly because i don't have the time to stay the whole sunday. Next year, I will stay the whole week-end in order to have time to attend all the speak i should be interested in.

The beer event was overcrowded, but all the beer i found there was great (in particular the Floris Pear). It was also a great time to have a demonstration of the XO OLPC laptop. This little thing is funny, but i don't get the way the UI should be used. Another bad point, is that the first console allow to login as root by pressing "Enter" (at least on the one i try). I suppose this kind of device is not intended to be secured.

I also have time to talk with some Debian people and some other people -- in particular one who was thinking that Windows 2000 is the best ever OS. At least, it means that there were people from different horizons -- and this is a good thing.

During Saturday, i spend half of the day in the big amphitheater (Janson). The talk about Tux with Shades (Linux in Hollywood) was impressive, regarding the trailer they show us... The talk about FreeBSD was interesting -- but not impressive as a trailer.

I spend Saturday afternoon in the Debian devroom, following all the different talks. I miss the one from MadCoder about managing packages with git... That's a shame because i really want to see this one.

Since my train was at 12am on Sunday, i choose to only pay a visit to the different booths. I have the pleasure to have a demonstration of the EeePC on the Debian booth that really please me. I found the UI more easy to understand than the one from XO. Speaking with the person demonstrating the laptop, she explained me that EeePC is more "standard desktop" and XO more "creative desktop". Conclusion: i am not creative ;-)

Also talking about everything around talks and the meeting, i think Bruxelles is a really nice city for this kind of events. ULB is not near the center of Bruxelles but there are enough transportation. There was really a lot of people attending FOSDEM, and this is a good thing. I also have the pleasure to find some people from the OCaml Meeting.

On January 26th 2008, the OCaml community has its first meeting in Europe. There was 5 different talks, including one from me. The meeting was pretty constructive and i think some great things should come out of it. In this post, i will focus on the Debian maintainer point of view.

The meeting was organized by me, with the help of Garbriel Kerneis and Vincent Balat. I wish to thank Mme Turgis from ENST/ParisTech who has made possible all this to happen.

Introduction:

I announce the creation of OCamlCore, a SS2L. It will provide commercial support for OCaml and related products. It will also provide community with some resources (including a GForge, a planet, some SCM repository...)

For now, i will open administration to Debian people who wish to help (for root rights) and from the whole community for other task (gforge and general administration). For now, i will choose alone who can administrate and who cannot... This is not a very open position, but this server is also for my company.

Xavier Leroy give us a nice talk that has let us see some future direction:

• OCaml 3.11 will have native dynlink
• hope to integrate GHC like type system (GADT: Generalized Algebraic Data Types)
• need to work on parallelism, following different paradigm

But above all, Xavier talked about the fact that there is a lack of manpower at INRIA and invited the community to build tools and other things (including a CPAN like distribution) to make the language more widespread. He also stated that a lot of things will stay in place in the name of backward compatibility.

OCsigen

Vincent Balat has given us a nice talk about OCsigen, a new framework for programming web application. This program is already in Debian and it is at the root of Debian discussion about moving .cm[ao] into libxxx-ocaml package. This new framework allows to program web application using continuation, which should ease a lot of aspect. It also features static type checking, including static verification of the generated HTML pages.

GODI

I was impressed to see G. Stolpmann coming to the meeting. Unfortunately, i cannot follow the whole talk, since i have some phone call to make, in order to book the restaurant. From what i have seen, it seems that GODI is growing, in term of manpower. They have some issues with OCaml 3.10, because of camlp4 and some packages. At the end of the conference, he was pushing for a more general use of GODIVA. In particular, it requires to have a very uniform way of building software. It should be the foundation of a build standard for OCaml software. In my humble opinion, i don't agree on this point. Basically, its proposal was based on configure/make all, which is too C style way of doing. It is not bad, but just exclude ocamlbuild enabled software.

ocamlbuild

Nicolas Pouillard has made an introduction on how to use ocamlbuild. I have discovered how it was working, since i didn't have time to work on this topic. It seems a good thing. I hope to be able to try it at some point. The conclusion was about modifying ocamlbuild to allow the use of multiple plugins. For now, the plugin is a separate file which is compiled first and then loaded, as a special case. Nicolas is looking for a full OCaml way to handle this for multiple plugins.

OCaml in Debian

I have spoken about different aspect of Debian packaging. After a short introduction and some history about OCaml in Debian, I come to some conclusions/problems:

• we have an early integration, which makes Debian handle a lot of packages, but this is due to a long history
• we still are not able to cope with libraries incompatibilities when rebuilding, we only have addressed ocaml package ABI problem
• the debian package management system is not really compliant with the OCaml way of creating libraries, which is our main problem
• native compilation is broken on 3 arches (Xavier Leroy told us that this should be solved for ARM)
• use of Alioth has made us more efficient to integrate packages
• Debian team are working by step: from time to time we begin to integrate a lot of packages, mostly because of some maintainers wishing to integrate a software with a lot of dependencies

Talking with Xavier give me some additional informations:

• ARM is fixed, it should compile with Debian stable on ARM, he explains that the problem is related to the multi ABI flavor of ARM
• he says that we should not have any problem concerning bytecode stripping of executable, if there is still some we should find the OCaml library that triggers this behavior
• I realize that this behavior can be triggered by ocamlmakefile, that still have a "-custom" option
• he promises me that he will send me a simple test to find custom bytecode application (combination of "file X" and a specific string at the end of the file)

At the end of the presentation, there were some questions. I discover that many people are ignoring the ABI problem with OCaml and its libraries. They seem to discover that it requires regular rebuild of our packages.

I also have a discussion about the fact that Debian binary distribution doesn't fit developers need. It seems that developers prefer to have the source of libraries they compile and also the most recent release. But at the same time, people avoid using GODI, which also have the problem of needing to wait for a particular library to be released... After some discussion, I point that some companies prefer to live in a frozen world, which Debian stable can provide. Living in a frozen world helps company developers to have the same environment from the beginning to the end of a project - which can last years. It also help to avoid build environment de-synchronization between company developers.

There was also a question about interaction between installed OCaml package and GODI software. I cannot answer it, expect with a "patches are welcome".

OCaml on a JVM using OCaml-Java

Xavier Clerc explained us how he has achieved running a full OCaml environment on a JVM. This work was pretty impressive, because he was able to compile OCaml top level and provide it as an applet. This is something amazing (and working). He stated also that this should allow to do some binding with java graphical user interface from OCaml. I was pretty busy with a phone call (to a restaurant for the dinner), so i don't have attend the whole conference. Anyway, the project is promising, but it needs to recompile every library using its compiler. I think this is not suited for Debian for now.

Workshop

The workshop was shorter than it should have been. This is due to accumulated time shift during the day. However, it was pretty interesting, because everybody can talked almost freely.

The initial discussion was about the "Unicode situation". This was a question about Unicode in Unison, but there is no real solution about it. For reader information, unison has problem with filename containing UTF-8 char. In particular when syncing two directories which are on two file system with a different encoding on each. Even if the file can be represented on the two file systems, the comparison (between UTF-8 and ISO8859-15) fails. This is because the comparison is a byte to byte comparison.

We discuss further the idea of OSR (OCaml standard recommendation) which was briefly discussed in the morning. I think David Teller (who have also done a great part of the IRC retranscription) was very keen on this idea.

I invited Nicolas Pouillard to discuss the three following subjects.

About camlp4 documentation, Nicolas told people about the he set up. About ocamlfind and ocamlbuild, he went back to the multiple plugin problems. About ocamlbuild and GODI, Gerd, Nicolas and Xavier tried to build a list of what metadata can be shared. This includes list of files to be installed (PLIST in GODI).

Concerning the "feedback from the Gallium", Xavier explains that he has done this in the morning (which is true). I think that Xavier implicitly agreed on the fact that if this kind of event happens again, he can do another talk about future of OCaml.

Concerning Summer of Code, I just remind that people can write description of Google Summer of Code project in the cocan wiki. Another one remind about Jane St Capital summer of code.

Points concerning common interfaces raise the discussion about OSR.

The organization of next year events doesn't raise particular interest. I think people would be interested to have one next year, if something comes out of this meeting.

After 2 weeks of my new life, i just found time again to write this entry.

I think that some people were enjoying the new year when my wife and I were also waiting for our baby.

He is born at 3:30 am on 2008/01/01.

Happy new year!

Yesterday, i decided to activate the so-called RAID 0 support on my P4P800 mainboard, to increase the performance of my 2 Seagate SATA disk -- bought for this purpose. The first unfortunate event was to discover that there is 3 levels of hardware RAID: controller, accelerator and fake. Of course fake RAID is not the better category and it is the one provided by my mainboard. Once, i have understood that i must use the package dmraid to activate my RAID, i fall into a syslog flood of messages concerning "attempt to access beyond end of device".

The problem is simple, the partition table are stored on the first disk of the RAID. Linux believes that he can reach the end of the device defined in the partition table of the first disk. But since, the partition table is for the whole RAID, it cannot access the last partition.

In fact, the solution is quite simple and described here . You must add files to udev and hal rules to ignore the partition found in the partition table of the first disk:

/etc/udev/rules.d/000dmraid.rules

KERNEL=="sda1", OPTIONS+="ignore_device"
KERNEL=="sda2", OPTIONS+="ignore_device"
KERNEL=="sda3", OPTIONS+="ignore_device"

(where sda1/2/3 are the partition stored on my RAID)

/etc/hal/fdi/preprobe/000dmraid.fdi

<?xml version="1.0" encoding="UTF-8"?>

<deviceinfo version="0.2">
  <device>
    <match key="scsi.model" string="ST3160811AS">
      <merge key="info.ignore" type="bool">true</merge>
    </match>
  </device>
</deviceinfo>

(where ST3160811AS is my two Seagate disks)

You should not ignore the whole disk in udev -- as i think it is suggested in the spanish web page (i don't speak spanish so i really don't know what it explains). After adding this two files, you must update your initrd:

update-initramfs -u

If you have problem with this configuration (you have ignored too much things), you can go back to the former initrd from grub command line, by editing the menu entry and editing the standard initrd to add ".bak" at the end.

At least, i got what i want:

~$ sudo hdparm -Tt /dev/mapper/isw_dhgabfaiad_RAID_Volume1

/dev/mapper/isw_dhgabfaiad_RAID_Volume1:
 Timing cached reads:   1354 MB in  2.00 seconds = 676.78 MB/sec
 Timing buffered disk reads:  426 MB in  3.01 seconds = 141.51 MB/sec

Not that bad for an old P4.