Am Mittwoch, 13. September 2006 11:07 schrieben Sie:
Daniel Fischer wrote:
Most certainly not. I'm pretty sure this is to a bug in your code. Something retains a data structure which is actually unneeded. Probably
Apparently. And my money is on a load of lines from the file (of which I need only the first and last Char).
Then you're doing it wrong[TM]. You shouldn't need to keep any part of
Yes, I did it wrong, but I didn't keep anything (but the first and last Char of each line) in memory on purpose. I hoped for the lines to be read one after the other, head and last extracted - possibly immediately passed to accumArray, but I wouldn't necessarily expect that - and the already used lines thrown in the dustbin on next GC. Maybe the compiler couldn't figure out that it wouldn't access these lines anymore.
the input in memory. Whatever it is, nobody can tell you without seeing the code. Try heap profiling, should you have no idea where to look for leaks.
Profiling (hy,hc) shows that the IO part of the programme holds on to tons of lists - that couldn't be anything but parts of the file-contents, I believe.
How could I solve the problem without representing the graph in some way?
By using an advanced tool called "brains". Sorry for not being more specific, but that's actually the fun part of the challenge and I'm not going to spoil it for you. ;-)
Forgive the stupid question, but where if not RAM would the chunk currently processed reside?
Oh, I overlooked "chunk". Well, yes, the "chunk" currently processed needs to fit into RAM. But how much of a problem could a single Char pose?
Well, if it's the last straw... But not much, I presume and even though it might be that we must have a few thousand Chars inmemory, that shouldn't do much harm either.
Donald Bruce Stewart wrote:
I agree. Some problems simply require you to hold large strings in memory. And for those, [Char] conks out around 5-10M (try reversing a 10M [Char]).
Sure, this one just isn't of that kind.
Yes, but I didn't tell the compiler :-(
Udo.
Cheers, Daniel -- "In My Egotistical Opinion, most people's C programs should be indented six feet downward and covered with dirt." -- Blair P. Houghton