May 122013

I think one reason I’ve been avoiding posting to my blog lately is the time commitment of writing something of decent length. To get over this hump, I’m going to shift my focus to writing smaller little discoveries of things I find during my researches into Haskell and technology. Let’s see how that goes.

 Posted by at 7:43 pm
Sep 062012

To show just how significant parallelized algorithms can be, today I discovered pxz, a parallelized version of the xz compression utility, which I use constantly. The proof is in the numbers:

Command Before After Ratio Time
xz 2937M 305M 0.104 32m
pxz -9e 2937M 281M 0.096 4m(!)

I put this alias in my .zshrc:

alias tar='tar --use-compress-program=pxz'

Note that to build pxz on the Mac, I had to comment out a reference to MAP_POPULATE, which the OS X’s mmap function doesn’t support.

 Posted by at 3:01 am
Oct 302009

I’ve seen this issue mentioned in some random and hard to reach places on the Net, so I thought I’d re-express it here for those who find Google sending them this way.

UPDATE: According to the discussion at, the real problem here is not fully dynamic string, but the use of _GLIBCXX_DEBUG. So I recommend ignoring what follows, as it will help you on Snow Leopard or Lion with gcc 4.6 and above.

Continue reading »

 Posted by at 4:35 am