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Editorial

Journal Journal: Open Source Press Relations

In my copious free time, I pretend to be a journalist. Aside from ranting on Slashdot, I have a couple of weekly-ish columns that I fill with opinions. In the last six months, I have tried to write articles about the BSD family. In preparation for these, I emailed members of the projects with some questions. The differences in the replies were quite surprising:
  • OpenBSD: The team gave me some really good feedback. Not everyone replied, but those who did gave some very interesting material.
  • NetBSD: I'd not used NetBSD much (a bit on some old SPARC32 machines), so I needed a lot of input here. The people I contacted forwarded my questions on to others, collected replies and gave me a huge amount to work with.
  • FreeBSD: This was my major disappointment. I've used FreeBSD for ages, and was looking forward to writing the article. I sent a message to their release engineering mailing list saying I would be interested in writing an article about the next release, and asking for input. It was ignored for a month, then I got one reply suggesting some people to contact. The only one of these to reply did so with a flame. I cancelled the idea of a FreeBSD article as a result, since I wasn't in the right frame of mind to write anything good about the project afterwards.
  • DragonFly BSD The only person I bothered contacting was Matt Dillon, since DragonFly is really his baby. Matt responded promptly with incredibly detailed answers. I'm still in the middle of writing the DragonFly article, but it's a lot of fun to do.

The NetBSD and OpenBSD articles got between 15-30K unique readers in the first seven days. I don't have figures for after that. I've been contacted by a few people who said they started using NetBSD as a result of the article. The moral of this story? If you want free publicity, try being polite.

User Journal

Journal Journal: House of Commons Technology

A little while ago, I emailed my MP about the report published by the BBC saying how great it would be if they made their programming available online using Windows Media DRM (just as the EU is prosecuting Microsoft over exactly that product).

Today, I got a reply, saying:

Thank you for your communication of the
1/2/2007, By E-Mail
which will receive attention

Now, normally, I would expect a reply of this nature to be sent by email, since it's basically an auto-responder. In this case, however, it was sent via a different mechanism. Second class mail.

Yes, my MP employs someone to act as an email auto-responder, replying by postcard to all emails. Isn't technology great?

Technology (Apple)

Journal Journal: Apple Discontinues Mail-in Repairs in the UK 2

Apple have quietly discontinued their mail-in repair service in the UK. While the terms of the AppleCare agreement still state that they offer it, and on-site repair in some cases, they have closed their repair centre and are telling customers to take their machines to the nearest authorised service centre. These are few and far between in the UK; for a lot of people the nearest one is several hours away.

Ping Wales have the full story. From the article:

A straw poll of businesses in Wales which use Macs reveals that no business customers have been informed of the change to the repair service.

Apparently customers were not the only ones kept in the dark over this:

Apple resellers in the region told Ping Wales that they hadn't been informed of the change either, adding that this did explain why the number of repairs coming in had increased significantly over the last few weeks.

User Journal

Journal Journal: Frits Post!

Last week, at a conference, I met someone called Frits Post. He seemed like a really nice guy, but I couldn't help wondering if he regularly posted here...
AMD

Journal Journal: Who Makes Nice Opteron Systems?

I have been told the I am allowed to spend some equipment budget on a nice dual processor system. I am doing work that requires more than 4GB of address space and would benefit from good threading performance. As far as I can see, this means Solaris on Opteron (much as I like SPARC, it doesn't cut it in terms of price / performance for machines under about 8 CPUs these days). Oh, and I need good floating point performance, which rules out Niagara.

Can anyone recommend a good supplier for Opteron machines at a reasonable price? I need a minimum of two CPUs (or cores), a reasonably sized (but not necessarily fast) hard disk, a couple of GB of RAM. It's going to run headless, so no graphics card is required (the Sun workstation line looks nice, but I object to spending money on an nVidia Quadro card that is never going to be used).

User Journal

Journal Journal: Aeron Chair!

Several years after the dot-bomb, I finally realise what all of the fuss was about with regard to Aeron chairs. I am currently visiting The University of Utah to collaborate with a researcher here and today I replaced the default chair I was using with an Aeron chair from an unused office. It is incredibly comfortable, and made even better by the fact that my supervisor doesn't have one.

On the more geeky side, there are a couple of large SGI SMP boxes (one 60 CPU, one 30) for me to play with and a Linux cluster.

Today we warned the technicians that we might need to use a big chunk of disk space. We were told that there might not be enough, since they only had about 200GB free on the RAID array we wanted to use (the one local to the 60 CPU box). Back home, our technicians complained when I dumped a 2GB DVD image in my home directory...

GNUStep

Journal Journal: Slashdot's incessent rejection of Gorm 1.0 submissions

Why does it seem as though slashdot does not accept GNUstep news. I suppose it's not KDE or GNOME, so it's not worth worrying about. I find it unbelievably frustrating to not be able to get a word in edgewise about the release of Gorm 1.0 here at slashdot. I believe that this site has become so full of itself that it thinks it actually has an effect on how things go in the Free Software/Open Source community or that what does and does not get on this site counts for shit!

Jeez.

OS X

Journal Journal: OS X Thread Performance

There have been a lot of arguments recently about why OS X sucks for some things, and the blame is often laid at the door of OS X's threading performance. This seemed odd, since OS X gets its threading system from Mach, which was designed to support threading from the ground up. As it turns out, the reason is somewhat more subtle.

OS X sucks at system calls. Due to the Mach+BSD kernel design, system calls are very expensive on OS X. On Mach, the system call cost is around 10x the cost on BSD - on OS X it's some combination of the two depending on what you do. The next thing to realise is that all of the POSIX thread synchronisation mechanisms are implemented using Mach-level synchronisation primitives. This means every time you lock a mutex (for example) you need to dive down through the BSD layer to the Mach layer. This gives you the horrible overhead of checking the permissions on a Mach port (something that sane Microkernels like L4 abandoned), and is expensive. This makes locking operations on OS X much more expensive than on BSD-like kernels. This, in turn, can make threaded code much slower. If you are Adobe, and you are rendering an entire image transformation in a small number of threads, then you will only lock at the beginning and the end of the operations, so it will be nice and fast. If you are doing low-level parallel operations for scientific computing (when not bitching about the OS X kernel), then you should really try harder to persuade someone to buy you a nice Solaris box.

User Journal

Journal Journal: Why I like Objective-C

Today, I wrote some code that enumerates, at run-time, all of the classes which conform to a particular protocol (that's implement a given interface, for any Java programmers) and allows the user to select one.

This is why I like Objective-C, and why using languages like C++ feels so painful in comparison. Oh, and for reference, enumerating the classes was around half a dozen lines. Sure, this kind of thing is possible in C++, but only if you build a huge amount of extra stuff on top.

Hardware Hacking

Journal Journal: Would You Buy Open Source Hardware? 3

I have recently become interested in the concept of open source hardware. It seems that you can buy FPGAs which provide a reasonable amount of performance for a relatively low cost. This means that you can implement your own CPU etc. designs in Verilog / VHDL. Places like opencores.org allow collaborative work on these designs, and so you can even download someone else's CPU design and use this.

This is all well and good, but FPGAs don't offer the same feature density as even ASICs (although they are re-writable), so this raises the question of whether it would be commercially viable to do a run of ASICs based on an open core, with a motherboard also based on an open design. Would you buy a motherboard / CPU that could run, for example, NetBSD and was entirely open source? How much of a premium would you be willing to pay for such a thing?

I really like the design of the Alpha CPU, and I would be interested in a machine that had a similar core design, and maybe willing to pay around a 50% premium over x86 for the elegance of the system - particularly if I could also download the core design to an FPGA, modify it, and submit changes back for inclusion in the next revision.

One of the real advantages of open source software is that it can easily be compiled for multiple architectures, so once you've written a GCC back-end and a boot loader for your system you suddenly have a huge amount of usable software.

I am rapidly coming to the conclusion that the ideal CPU would have a very simple instruction set, and not even do out-of-order execution. Code running on it should be compiled first into some kind of byte-code, and any re-scheduling should occur in the bytecode JIT - move as much complexity into software as possible, since it's much easier to upgrade (and to configure at run-time).

Portables (Apple)

Journal Journal: Out of koolaid error

Apple make shiny toys, there is no denying this. It is a shame that their customer support and build quality are so dire. About a year ago, I decided I should send my PowerBook in for repairs. It was not an easy decision, there were a few things wrong with it (white spots on the screen, one of the SO-DIMM slots not working, detection of headphones had an intermittent fault), but nothing that made it unusable - and I used it a lot. Never mind, I thought, it usually only takes them two days to do a repair, so I'll back everything up, grit my teeth, and send it in.

A month later they finally admitted that they'd lost it. A month after that they got around to replacing it. The one they replaced it with didn't even boot. They collected it and fixed it relatively quickly, leaving me with a new machine which had a fault in one of the SO-DIMM slots.

At this point, I decided not to send it back in for repair again. I'd already wasted around 10 hours on hold to Apple's customer support, and I didn't want to spend any longer.

Now, however, the fault with one slot has become an intermittent fault with both. Moving the machine at all causes memory errors (and will cause it not to resume from standby). When I boot, I have no idea which RAM slot will be operational (I've put a stick in each - sometimes I boot with 512MB, sometimes with 256MB. So far, I haven't managed to boot with 768MB, but there's hope...).

I am going to try to borrow a machine from the department while I wait for this one to be repaired. If I am really lucky, I'll be able to bring it home and work from here. Well, I can hope...

User Journal

Journal Journal: New Toys And More On The Mini

This week I got some new toys. I think my supervisor is feeling guilty (been seeing other students, or something), and practically forced me to spend some grant money on shiny things. These were:
  • An Apple 23" Cinema HD. Very nice. I'm using it now. I have so much screen space that I can actually see my desktop in several places (unlike my physical desktop, which is covered with things).
  • A LaCie 500GB disk (which is really 466GB). FireWire 800, with FW400 and USB2 as well (although you can only chain them with FW800). I have a 320GB (300GB) one at home, which I use for video editing. This one is for storing large data sets, and definitely not for video editing, oh no. Honest.
  • An iSight. Officially so I can join video conferencing meetings with the other 3 sites we work with on my laptop.
  • A BlueTooth Keyboard (Apple) and mouse (Kensington - 3 buttons!) so I don't need to plug in lots of wires when I plug in my laptop.

I suddenly have an incentive to stay at my desk (apart from the view of the sea).

In unrelated news, I mentioned previously that I was putting OpenBSD on a co-located Mac Mini, and would be writing about this. The first 4 of these are now online:

Macs in a rack - taking the mini to the masses
Why OpenBSD?
Setting up secure mail on OpenBSD
Filtering Spam with OpenBSD

The fifth one (Web and Webmail) is done, but will not be release until next Friday (it's my birthday next week, so I wrote it early). The sixth will cover setting up a Jabber server. I haven't yet decided what the seventh will cover - suggestions welcome...

Oh, and the hosting place has agreed to give a discount to Ping Wales readers, so don't forget to mention Ping to them if you do decide to use them (details in the first article).

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