Monday, March 30, 2009

6GB on 32-bit linux

Well, it all started when a friend said their SMT (statistical machine translation) system was ready to download and install. He then casually mentioned it is a bit of a memory hog, "4Gb minimum, 8Gb preferred".

Wow. I looked at my up-until-then-perfectly-adequate-some-might-even-say-overkill 2 gigabytes and felt like a salesman who had just been told he ought to upgrade his sensible car for a sports car in order to look more successful!

I have dual-channel, and two slots free. Another 4Gb was under 5000 yen at Dospara (Japanese only), where I had bought this computer, so I emailed them to confirm it would work. After a few emails, and a bit of research I found out:
* Windows 32-bit will only go up to 3Gb.
* 64-bit Windows, 64-bit Linux are both fine well beyond 8Gb.
* 32-bit linux will allow up to 4Gb per process, and can use more than 4Gb altogether.

(I wanted to stick with 32-bit linux, as Flash is critical to my work and has no 64-bit version.)

Dospara were rather cautious, saying they don't support linux, but I went for it. When I plugged in the extra 4Gb, the bios correctly recognized 6Gb. Then Ubuntu said I had 3Gb. But that was okay, as I'd been expecting it. I went to the package manager and selected the "linux-server" meta-package, then rebooted.

Drum roll please: "free" reports I have 6Gb available. I'm using 475 Mb, and have 5,745 Mb free. See, I told you I didn't need it. But this is city driving. You wait until I take this beast down the local Formula One track, otherwise known as Difficult AI Problems.

Oh, while I was there I also bought a 1Tb SATA drive. Yes, that is a "T". A whole terabyte in a little, diddy box. It was only 10,000 yen (you could get one for 7,880 yen if you go for Seagate, but a quick bit of research showed lots of unhappy people, so I went for Western Digital which seemed to be the reliability brand).

What do you mean: "I bet he doesn't need that much storage either" ? Just because my current 250Gb drive still has 143G of free space after 18 months, doesn't mean I suddenly won't need more capacity...

And you can bet that when the ladies hear I am part of the Terabyte Generation I'm going to be fighting them off with a stick. Oooh, yeah! I am so sexy.


keith.s.wilkinson said...

Fedora 11 is now in Beta. Its feature list
says that the x86_64 kernel will be installed and used on compatible hardware, even when installing a 32-bit OS.

darren said...

Hi Keith,
Strangely the link goes to
which doesn't mention 64 bit, but instead just targeting 586 instead of 386 architecture. Which sounds much more useful.
64-bit kernel seems to not be needed unless you need a single process to have more than 4GB. Certainly for desktop installations the compatability downsides (such as flash, and almost anything else that is closed source) would be unpopular.

darren said...

Having said I didn't need that much memory, outside of exotic AI apps, I was then sent a log file to analyze, which was 927MB. Being able to open it in SciTE made checking it easier.
free tells me I have 4.9G used when I open it (2.2G of that by SciTE; apparently SciTE is also using 100% of one CPU, though jumping around the file is not at all sluggish).
(For those who like to play editor wars, vi opened it only using 1G and 30% CPU, but this file contains binary characters and SciTE displays them much more attractively.)

Jim Tittsler said...

There is a 64-bit Flash plugin for Linux (only :-), although it is still called an "alpha prerelease".