I was having a discussion with one of the guys who decided to contribute to the development of mutella on the subject. I just paste a quote here to save myself typing...
Quote:
>> Anything that results in a block of your heartbeat thread during its
>> operations will result in a lock on all activities pending during that
>> poll() call.
>>
> Care should be taken to omit blocking calls. There is none at the moment,
> or nearly so.
>
Any execution of a gethostbyname() call can result in a nameserver lookup
which, if delayed, will cause problems. That's used heavily at the moment,
and while this can't necessarily be avoided, it does need to be moved out of
the critical path; Darwin has some latency problems in specific NAT
environments and DNS proxies at the moment with that, and I can imagine that
there would be ways for it to cause problems for others as well.
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So, what to do with "gethostbyname"? It may REALLY block for few seconds if not more. Cashing results of the name resolution will help somehow, but not entirely... because every now and again it might be needed to look up something completely new... Well, I can hardly think of anything other than host-servers, and in this case caching will help, but still, this does not seem to be elegant.
Secondly, what about matching the list of local shared files against the incoming queries? This task needs to be done in the backgroung, which implies a worker-thread needs to be used. Am I right?
--Max