More Zonkyness

Author: Mike Meredith

  • Film Review: Apocalypto

    Format: DVD

    IMDB Entry: here

    An entertaining man-chase through the jungle of pre Columbus central America. The hero of the story is taken from his village by slavers to a Mayan city where he only just misses being sacrificed, escapes and is pursued through the jungle by the men who captured him. An added twist is that his wife and child are hiding from the slavers in a hole in the ground and can’t escape from it without his help.

    It is a pretty good film, but I was a little disappointed it was not better … given the claims for it. I think because it is a rare example of a film covering pre-Columbus America which did not compromise by insisting on making the audio language Mayan. Everyone then was under the impression that this was the film on Mayan civilisation, and the reality is somewhat less so. We only see a quick snap-shot of Mayan civilisation … perhaps 10-20 minutes of the length of the film.

    The film however is pretty good but doesn’t quite come up to an epic portrayal of Mayan civilisation. I guess we will have to wait for that.

  • IT: Linux, ZFS and Open-Source Licenses

    If you’re hoping to read about Linux finally getting ZFS (except as a FUSE module) then you are going to be disappointed … this is merely a rant about the foolishness shown by the open-source world. It seems that the reason we won’t see ZFS in the Linux kernel is not because of technical issues but because of licensing issues … the two open-source licenses (GPL and CDDL) are allegedly incompatible!

    Now some may wonder why ZFS is so great given that most of the features are available in other storage/filesystem solutions. Well as an old Unix systems administrator, I have seen many different storage and filesystem solutions over time … Veritas, Solaris Volume Manager, the AIX logical volume manager, Linux software RAID, Linux LVM, …, and none come as close to perfection as ZFS. In particular ZFS is insanely simple to manage, and those who have never managed a server with hundreds of disks may not appreciate just how desireable this simplicity is.

    Lets take a relatively common example from Linux; we have two disks and no RAID controller so it makes sense to use Linux software RAID to create a virtual disk that is a mirror of the two physical disks. Not a difficult task. Now we want to split that disk up into seperate virtual disks to put filesystems on; we don’t know how large the different filesystems will become so we need to have some facility to grow and shrink those virtual disks. So we use LVM and make that software RAID virtual disk into an LVM “physical volume”, add the “physical volume” to a volume group, and finally create “logical volumes” for each filesystem we want. Then of course we need to put a filesystem on each “logical volume”. None of these steps are particularly difficult, but there are 5 seperate steps, and the separate software components are isolated from each other … which imposes some limitations.

    Now imagine doing the same thing with ZFS … we create a storage pool consisting of two mirrored physical disks with a single command. This storage pool is automatically mounted as a filesystem ready for immediate use. If we need separate filesystems, we can create each with a single command. Now we come to the advantages … filesystem ‘snapshots’ are almost instantaneous and do not consume additional disk space until changes are made to the original filesystem at which point the increase in size is directly proportional to the changes made. Each ZFS filesystem shares the storage pool with the size being totally dynamic (by default) so that you do not have a set size reserved for each filesystem … essentially the free space on every single filesystem is available to all filesystems.

    So what is the reason for not having ZFS under Linux ? It is open-source so it is technically possible to add to the Linux kernel. It has already been added to the FreeBSD kernel (in “-CURRENT”) and will shortly be added to the released version of OSX. Allegedly because the license is incompatible. The ZFS code from Sun is licensed under the CDDL license and the Linux kernel is licensed under the GPL license. I’m not sure how they are incompatible because frankly I have better things to do with my time than read license small-print and try to determine the effects.

    But Linux (reluctantly admittedly) allows binary kernel modules to be loaded into the kernel and the license on those certainly isn’t the GPL! So why is not possible to allow GPLed code and CDDLed code to co-exist peacefully ? After all it seems that if ZFS were compiled as a kernel module and released as a binary blob, it could then be used … which is insane!

    The suspicion I have is that there is a certain amount of “not invented here” going on.

  • Computer Security

    The UK news this morning (and last night) had an item on about plans to tackle the problem of phishing with various suggestions (most of which make sense). Similar stories about phishing and how people are being ripped off by fraudsters regularly come up on the news. One thing that rarely gets a mention except in passing with a suggestion to run a ‘protected computer’ is how regular computer users who ignore security are contributing to the problem.

    Almost all spammers (and phishers) these days use botnets to spew out their sewage; as someone who runs a mail server for a large organisation I regularly take a look at where spams entered the Internet mail system. In the vast majority of cases it has entered via a location that is obviously a client machine operated by an ‘innocent’ person ignorant of what their computer is being used for.

    There are plenty of places to point the finger of blame …

    • The companies who produce operating systems that are so vulnerable to being compromised when connected to the Internet.
    • Those who use viruses and worms to create ‘botnets’ of vulnerable machines to be used for a variety of purposes.
    • The ISPs who irresponsibly fail to block outgoing mail not going through their mail servers. Whilst some (me!) should be able to opt out of such a block because we (I) run our own mailserver it should not be open by default.

    Finally, the person who runs a computer irresponsibly is also to blame. Obviously not everyone wants to become a security expert, but there are a few easy steps to make it more difficult for your computer to be broken into. And they should accept that if they get infected they could get slung into a ‘quarantine’ … ISPs can and should be able to detect infected machines being used by spammers and sling them into a ‘quarantine’ network with limited functionality. This ‘quarantine’ is dead simple to setup, as I’ve done it myself.

    To reduce it to an analogy, if you were to leave a car parked with the handbrake left off are you totally blameless if someone leans against the car and it rolls down a hill and kills someone ? People tend to regard leaving an infected computer online as being a trivial matter; it is not.

  • Music: Instant Karma

    I accidentally heard a bit of Green Day’s cover of John Lennon’s “Working Class Hero” (probably through accidentally encountering it on YouTube) and immediately liked it enough to start hunting for it to buy. It turned out to be on a yet to be released CD called “Instant Karma” in aid of Amnesty International and their campaign against what is happening in Darfur.

    I immediately purchased it online and it turned up today. I haven’t had the chance to listen to it except for picking out a few obvious highlights. The cover by Green Day is worth the price on it’s own (even ignoring that much of the money is going to Amnesty) … I don’t normally like covers too much, but in this case Green Day’s version is better than the original. Those who know me, know that I almost always prefer the original version of a track, but Green Day manage to hit the right spot.

    Many of the other tracks are interesting particularly when you don’t know the artists involved. However whilst I normally like Avril Lavigne’s music, her version of “Imagine” is an utter disaster area.

    I’m not usually given to swearing in this blog, but this case practically requires it … those fucking fuckers at fucking Google have bowdlerised that fucking cool video by taking out the fucking “fucks”.

  • Bill Gates, OLPC Project, Educational Content

    Just seen part of an interview with Bill Gates on News24 where Microsoft’s educational projects were being discussed, and the One Laptop Per Child project was brought up. Bill sort of avoided trying to talk about it by claiming that hardware costs will continue to come down and the real problem is about educational content.

    It is true that hardware costs tend to come down … to a point where prices stay fairly static but specifications increase. He has also glossed over the fact that the OLPC laptop is semi-ruggedised with features specifically intended to help with its use as a learning tool rather than a working tool; including the special display which has a special low-power black and white mode intended for reading eBooks. Not something found in a typical laptop!

    The other thing that was totally ignored is that the Sugar user interface (running on a stripped down RedHat) is designed to be easy to use for children rather than rely on some conventional approach to desktop computing. For instance there is an easy way to see your local “neighbourhood” (press F1) … the local mesh of internetworked OLPCs.

    However Bill hit the nail on the head by bringing up the content issue. It is the real problem and in fact the OLPC project highlights this and has a prominent area on their Wiki to deal with content. Perhaps Bill should put his money where his mouth is and help fund the content projects … it may not help Microsoft directly (although given that the content is intended to be “open-source” there is no reason why a Microsoft operating system could not use it as well as the OLPC laptops) but it would help education.