Hi, On Samstag, 6. Juni 2009, Bas Wijnen wrote: > On Sat, Jun 06, 2009 at 09:58:24AM +0200, Martin Preuss wrote: [...] > > It can't have an infinite loop: It runs in a single thread and needs > > to do some cleanup from time to time (e.g. releasing readers and cards > > after some timeout etc). > > Actually, it can, if I understand your problem correctly. You are > saying that a forked child will eventually die and needs to be cleaned > up? If you don't ignore SIGCHLD, but handle it with an empty handler, [...]
No, that's not what I mean. Of course the daemon uses SIGCHLD to catch dying children (at least to prevent zombie processes). The cleanup concerns internal structures after using a card. The readers and cards are not disconnected immidiately after use (because sometimes cards and readers are opened and closed multiple times within a short period so immediately releasing a reader unnecessarily adds startup and shutdown time and therefore prolongs the execution time for the application). [...] > Right. And this is much better than running a lot, but it still means > it can never be in swap for long. If that can be fixed, it would be an > improvement. [...] The part which can never be swapped out is only the one or two pages which actually contain that code. So I guess we are only talking about 4 or 8 KB here. Of course this could be reduced to zero given the right amount of work but currently that's not my highest priority. Regards Martin -- "Things are only impossible until they're not" Martin Preuss - http://www2.aquamaniac.de/ AqBanking - http://www.aqbanking.de/ LibChipcard - http://www.libchipcard.de/
