Achill?
KDE Italy and me
I’m really honored to report that KDE-Italy site published an interview about me. You can find it here. Many thanks to Giovanni Venturi, webmaster and maintainer of kde-it.org!
No Redback
RPM Transaction Enhancements
One of the reasons I wanted to revive rcd was so that I could use it to play with some package management ideas I’ve been kicking around. One of these ideas is a way to reliably rollback changes made during an RPM transaction. That is, actually make RPM transactions transactional.
Recently, a colleague introduced me to device-mapper, a kernel system used for block device redirection. There is a really cool thing that uses it called dm-snapshot, which allows you to redirect all writes to a device into a separate device. What I would like to do is use this to store all of the changes made during an rpm transaction. I think it would just need a bit of patching so that it only stores the changes made by the rcd/rpm process (and children). If anything goes wrong, you can just trash the snapshot data and things are exactly as they were in the beginning. Of course, if it succeeds without problelms, you need to merge the snapshot changes into the original device. This is where things get fuzzy, as dm-snapshot does not have this ability. However, Mark McLoughlin has created a set of patches that add this feature as part of the Stateless Linux project. Sadly, the patches do not appear to be a high priority for the kernel guys right now, so I guess this approach will have to be put on hold.
In any case, a system for performing this rollback stuff would be ridiculously useful in general — not just for package management. It looks like it will be a little more than I can do by myself in a weekend hack, though, so hopefully someone else will carry the torch? :)
My rpmdb is back
Oops, I lost my rpmdb
Return of The Carpet
Red Carpet, that is. Yes, that Red Carpet. I’ve taken some time lately to give some love to our old friends rcd and rug (the original rug, not the rewritten one). First I got everything building on a modern distro (openSUSE 10.2). This took more effort than I thought it would, but eventually things worked well. After that, I set out to make rcd more usable with yum services. Here is a list of the main changes:
- Add native yum support. I removed the ‘helix’ service support and replaced it with something that understands yum metadata. This means you can just do ‘rug sa repo_url name’ for any yum service. I used the excellent yum parser that Tambet wrote for the libredcarpet backend of zmd to accomplish this.
- Remove channel subscriptions. Since yum services don’t provide multiple channels, subscriptions aren’t really necessary. They have been replaced with the ability to disable a service.
- Add sleep ability. One of the main complaints against rcd was that it used too much memory. This was mostly because over time the heap would become fragmented. The ‘sleep’ feature avoids this by running the main rcd daemon only when necessary. After a period of inactivity (3 minutes by default), the main daemon replaces itself with a smaller daemon. This smaller daemon simply waits until a request comes in and launches the full daemon to respond.
With the above changes, rcd is once again a joy to use. I would like to get the GUI working again, but there is some kind of threading problem preventing it from running. I would also like to add ftp support, but that is not a top priority.
I know there are probably SUSE users reading this asking “Ok, sounds fine, but is it fast?”. While it may not be the fastest thing out there, I think you will be surprised at the results (I was). Here are a few simple benchmarks from normal usage scenarios:
First, lets look at the number of services I currently have added:
% rug sl
- | Service URI | Name
—+———————————————————————————+——————
1 | http://go-mono.com/download-stable/suse-102-i586?r… | mono
2 | http://software.opensuse.org/download/FATE/openSUS… | fate
3 | http://ftp.suse.com/pub/suse/update/10.2/?name=upd… | updates
4 | http://download.opensuse.org/distribution/10.2/rep… | suse-nonoss
5 | http://download.opensuse.org/distribution/10.2/rep… | suse-oss
6 | http://packman.inode.at/suse/10.2?remote_only=1;na… | packman
7 | http://software.opensuse.org/download/home:/cybero… | cyborg
8 | http://software.opensuse.org/download/X11:/XGL/ope… | xgl
9 | http://software.opensuse.org/download/Beagle/openS… | beagle
10 | http://software.opensuse.org/download/games:/actio… | games
11 | http://software.opensuse.org/download/Virtualizati… | virt
12 | http://software.opensuse.org/download/home:/kraxel… | kvm
So 12 services, and the package count is almost 21000. 22500 if you also count the ones in the rpm database. How long does it take to load all of those?
Cold filesystem cache, daemon is sleeping:
% time rug ping > /dev/null
rug ping 0.17s user 0.02s system 1% cpu 13.735 total
14 seconds to respond isn’t terrible, considering the cold filesystem cache. Now that the kernel has it cached, though, how long does it take?
Warm filesystem cache, daemon is sleeping:
<blockquote
% time rug ping >/dev/null
rug ping > /dev/null 0.14s user 0.02s system 3% cpu 4.465 total
4.5, not bad. Definitely in the tolerable range, I’d say. Of course after the daemon is awake, commands respond immediately. That is maybe the only good thing about rcd being a daemon — subsequent commands are instant, where other tools (yum, smart, etc) have to load the package metadata again. Memory usage after rcd wakes up is about 28MB, so that is not too bad either (it is a little over 1MB when sleeping).
Packages for recent SUSE distros are available in the build service. It has had a hard time keeping up recently, though, so you may run into a problem or two with rug. Sources can be found in gnome svn in the yummy branch of the various modules (rcd, rug, libredcarpet).
Also, yes, I am sick sick person.
Hiking
Smart Documents.
Yesterday I started the evaluation of the Microsoft's ISmartDocument interface for Office2003.
I started in a clean VM. I installed:
* Windows XP
* Office2003 and
* DevEnv 7.1 (C#)
Then I downloaded and installed the Office 2003 Smart Document Software Development Kit (SDK)
Next I tried to compile the “SimpleSampleCS” from the SDK.
It failed.
Some research showed that I had also to install the Office 2003 Update: Redistributable Primary Interop Assemblies.
Finally I was able to compile the project.
Next I tried to activate the smart document by simply opening the “SimpleSample.doc” in Word 2003. I ran the “setpolicy.bat” script and then the “DisableManifestSecurityCheck.reg” file. Then I opened the “SimpleSample.doc” and was asked to “Download the XML expansion pack”. After answering the security question with “no” I was able to get the sample working. (Other orders of invoking the scripts lead to the failure of loading the expansion pack”. I took me quite a while to figure that out. I even installed the .NET 3.0 Runtime Environment --- but I believe that is not required.).
Finally I was able to see the following “SimpleSampleCS”:
The overall architecture of “ISmartDocument”s is based on custom schemata to which actions can be attached. Quite simple but I gives custom schemata a meaning of the end.
The question I'm interested in:
* How is this work related to alien attributes and metadata in ODF? And
* what do we have to do to provide a competitive environment in OOo and ODF?
Issues wrt. text grid in Issuezilla
Today, I happen to find that there are quite many text grid issues open in Issuezilla. I will look at them one by one and try to fix them. :)
Some issues wrt. text grid in issuezilla:
i53425:more flexibility in the grid layout
i73011:Chinese layout incorrectly with text grid
i40768:CJK:Register-true not activated for frames when importing; Grid layout
i53464:Word table reformatted shorter on import due to Grid layout
i15251:"Snap to Grid" doesn't work correctly
i29543:WW8: paragraph with "snap to grid" invisible in table
i15424:baseline in grid
i55461:snap to grid doesn't work correctly inside frame
i54864:WW8: Different treatment of tables in page due to active CJK Grid
i72657:A single line on Word got converted to two lines on Writer due to Text Grid
i68204:option "Print grid" becomes inactive when reopening Page dialog
i35684:[Text Grid] Vertical alignment for different font sizes differ from MS Word
i49214:CJK: Line spacing interpretation is different between Word and Writer due to text grid
i24195:WW Import: Cell height is too big when opened in OOo 1.1.1a (due to CJK-Grid)
i56820:Ruby in vertical text in grid wrongly moves original text sideways
Please let me know if anybody has question about text grid layout. :)