Compiling data

Simon Peyton-Jones simonpj at
Thu May 27 05:46:06 EDT 2004

GHC is indeed utterly terrible when compiling source files that contain
a lot of literal data.  This seldom bites (which is why we keep
postponing doing anything about it) but when it bites, it bites badly,
as you found.  There's some non-linear algorithm going on.

If any helpful person out there with a build-GHC setup would like to
build a profiled version of the compiler, and poke around a bit to
localise where all the time is going, that'd make it much more likely
that I'd do something about it.  It might even be trivial to fix, who


| -----Original Message-----
| From: glasgow-haskell-users-bounces at
| bounces at] On Behalf Of Ketil Malde
| Sent: 27 May 2004 10:41
| To: glasgow-haskell-users at
| Subject: Compiling data
| Hi,
| I've recently tried to compile some data into my program, and suddenly
| I realize why people tend to complain about the speed of GHC.
| For a benchmark, I'd like to include a bit of data in the form of a
| list of integer matrices (i.e. [[[Int]]]).  While I have about 10000
| them, sized about twenty square, even 100 of them takes extremely
| long to compile.  Is there a trick to make this faster?
| (For short lists (1-8 matrices), time seems to scale linarly, but the
| 100-matrix took much longer than expected from a simple extrapolation)
| Also, it takes a long time before any error is produced, it'd be nice
| if syntactical problems were reported as quickly as possible (perhaps
| they are?)
| -kzm
| --
| If I haven't seen further, it is by standing in the footprints of
| _______________________________________________
| Glasgow-haskell-users mailing list
| Glasgow-haskell-users at

More information about the Glasgow-haskell-users mailing list