[Caml-list] Re: gc overhead
Hello, On 03-03-2010, Edgar Friendly thelema...@gmail.com wrote: On 03/02/2010 06:09 PM, Warren Harris wrote: On Mar 2, 2010, at 2:03 PM, Sylvain Le Gall wrote: You can have a look at: http://ocamlviz.forge.ocamlcore.org Thanks! This looks very promising. I'll give it a try. Overall, good job. But is it going to die or stay maintained? Well, I hope it will stay maintained. At least source code, bugs and release on the forge will stay there for a long time (I can make promise on this part). And whenever current developpers become inactive, OCamlCore.org administrators can move ownership to other (with notice to current owner, of course): http://www.ocamlcore.org/philosophy/ (point 4) But anyway, this kind of tool is targeted at debugging on the first place. It is not a mandatory piece of a software/library. You can lie without it, when you have finished your job debugging/profiling your program. So I would say that long term maintainance should not bother user for now. It is actually something that is lightweight and that works. To my mind this is enough to consider using it. If a lot of people start using it, it is highly probable that it will stay maintained. Regards Sylvain Le Gall ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
[Caml-list] Re: gc overhead
On 01-03-2010, Warren Harris warrensomeb...@gmail.com wrote: I would like to determine what percentage of my application's cpu time is spent in the garbage collector (for tuning purposes, but also just to monitor the overhead). Is there any way to obtain this information short of using gprof? Additional information provided by Gc.stat would be ideal, or perhaps a Gc.alarm that was called at the beginning of the gc cycle, but neither of these seem to exist. You can have a look at: http://ocamlviz.forge.ocamlcore.org This allow to instrument your code and watch GC activity. I think that with a little a little help on program side, you can be quite precise about GC without using gprof at all. This should also be more lightweight than gprof. Regards, Sylvain Le Gall ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
Re: [Caml-list] Re: gc overhead
On Mar 2, 2010, at 2:03 PM, Sylvain Le Gall wrote: You can have a look at: http://ocamlviz.forge.ocamlcore.org This allow to instrument your code and watch GC activity. I think that with a little a little help on program side, you can be quite precise about GC without using gprof at all. This should also be more lightweight than gprof. Sylvain, Thanks! This looks very promising. I'll give it a try. Warren ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
Re: [Caml-list] Re: gc overhead
On 03/02/2010 06:09 PM, Warren Harris wrote: On Mar 2, 2010, at 2:03 PM, Sylvain Le Gall wrote: You can have a look at: http://ocamlviz.forge.ocamlcore.org This allow to instrument your code and watch GC activity. I think that with a little a little help on program side, you can be quite precise about GC without using gprof at all. This should also be more lightweight than gprof. Sylvain, Thanks! This looks very promising. I'll give it a try. Warren I'd like to add my personal experience with ocamlviz - it's a great program, and has helped me a ton find unexpected performance. It has very good functions for starting and stopping timers that the gui can monitor in realtime, and associating these with counts of how many times your program reached a certain point can give good understanding of function call cost. It's memory profiler makes a very pretty graph of how much memory is in use by your program. I've also gotten started using its ability to watch the live value of ref values to monitor the state of the program easier than [eprintf]s, especially monitoring the state of many variables at once. It's very fast and the ability to debug over the network has come in handy more than once. This said, I've wanted to measure GC overhead with it, and found it lacking in that regard. If anyone finds a way to do this, I'm interested. I've not done much with its tree viewer, and the hashtbl monitor only indicated that the Hashtbl.t I was using had an amazingly horrible hash, and was filling only 3% of its buckets, and had thousands of entries in a few buckets. I tried to fix the hash, but ended up switching to a Map. Lastly, the ability to mark in memory certain values and have it count the total usage and/or count of those values seems interesting, but gets quite slow. I've not had much luck with it. Overall, good job. But is it going to die or stay maintained? E ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
