Remember what I said before#

Thu, 01 Jan 2004 15:32:27 +0000

Remember what I said before Christmas about GC frobbing? With the new simpler region allocation policy described there, but no changes to static space usage :

• (time (dotimes (i 400) (gc)))

Evaluation took: 30.413 seconds of real time 30.354383 seconds of user run time 0.058991 seconds of system run time 0 page faults and 4939776 bytes consed. NIL

and in fact we can easily double that again by disabling the check for read-only objects and dumping everything in static space, so it looks like the write barrier stuff does make a difference. So why is CMUCL doing in 13 seconds what takes us 30 (the easy answer is "it has a better object/region allocation policy", obviously, but better why?) and how much faster would it be if it were also to remove purify-into-static-space?

In happier news, while thinking about tidying up today I found a Brian Aldiss novel I apparently haven't read yet.