On Mon, 10 Jan 2011 06:53:36 -0700 Matthew Flatt <mfl...@cs.utah.edu> wrote:
> At Sun, 9 Jan 2011 20:19:23 +0100, Stefan Schmiedl wrote: > > Well, that was about two hours ago. The reference GC instance is > > still idling away at 18330232 bytes, just as before, but the web server > > instance has "grown" from 47923392 (first GC of -672 bytes) to 47957512 > > (first GC of -672 bytes after last "real" GC), that's about 32kB. > > > > Somebody's snacking on my RAM here. > > There are many reasons that small amounts of memory may accumulate in > the short run --- especially caches and data structures that > periodically compact themselves. What I find interesting is that there are no such complex structures in the reference session I ran, but crop up in the web server session, even while it is not doing anything... > > Meanwhile, I'm not sure why you're seeing GCs at all when the server is > idle. The GCs unexpected, right? But if you're using the LRU manager, > it seems to call `collect-garbage' along with its collection routine. > ... except having around the LRU manager. Good point. I'll try using another manager and see if it makes a difference. But right now it looks as if the act of GC is causing a tiny leak. > For example, if I start Racket and just run `(collect-garbage)' in the > REPL, then after a while, I see a cycle of about 20 numbers around > -1000 and then one number around 15000. That effect seems to be from > the REPL allocating parameters that create weak boxes that are > referenced by a chain of records that are periodically compacted into a > hash table. The negative numbers don't quite balance the positive > numbers for the first many iterations of the cycle, because there's > another effect relate to rehashing (that will eventually compact a hash > table of weak boxes); I expect I'd see a larger positive number if I > had enough patience to go hundreds of times. Heh, that's why I asked earlier how to speed things up. If you look back at my (loop), you'll see that I'm calling collect-garbage every 10 s. > > It's always possible that you're seeing a real leak, but I think it's > at least as likely that you're just seeing the effects of complex data > structures in the run-time system. > It looks like it might be a while before I can spare some time for further investigations, but I'll keep in on top of my list. Thanks for the LRU idea. s. _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
