marlowsd: >> I'll work with Simon to investigate the runtime, but would welcome any >> ideas on further speeding up cafe4. > > An update on this: with the help of Alex I tracked down the problem (an > integer overflow bug in GHC's memory allocator), and his program now > runs to completion. > > This is the largest program (in terms of memory requirements) I've ever > seen anyone run using GHC. In fact there was no machine in our building > capable of running it, I had to fire up the largest Amazon EC2 instance > available (68GB) to debug it - this bug cost me $26. Here are the stats > from the working program: > > 392,908,177,040 bytes allocated in the heap > 174,455,211,920 bytes copied during GC > 24,151,940,568 bytes maximum residency (6 sample(s)) > 36,857,590,520 bytes maximum slop > 64029 MB total memory in use (1000 MB lost due to fragmentation) > > Generation 0: 62 collections, 0 parallel, 352.35s, 357.13s elapsed > Generation 1: 6 collections, 0 parallel, 180.63s, 209.19s elapsed > > INIT time 0.00s ( 0.11s elapsed) > MUT time 1201.47s (1294.29s elapsed) > GC time 532.98s (566.33s elapsed) > EXIT time 0.00s ( 5.34s elapsed) > Total time 1734.46s (1860.74s elapsed) > > %GC time 30.7% (30.4% elapsed) > > Alloc rate 327,020,156 bytes per MUT second > > Productivity 69.3% of total user, 64.6% of total elapsed
Well done!! _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
