[no subject]

David


On Thu, 16 May 2002, Tim Muller wrote:

> Hi,
>
> I'm writing on a server based on gnetlib/glib for linux that needs to handle
> a large number (500-5000) of not necessarily very busy connections. The
> "churn" rate of these connections is fairly low (i.e. maybe 1% are
> disconnected and/or newly established in any 1-minute interval or so).
>
> The application should be single-threaded, and will use GServer* for the door
> port and then work with the GConn* callback as these connections are accepted.
>
> As far as I know glib, and thus gnet, uses poll() and/or select() in order to
> find out whether events have occured on a set of filedescriptors, rather than
> signal-driven asynchroneous I/O notification possible from linux 2.2 kernels
> onwards (which would be far more effective, because a signal is sent to the
> process whenever an event occurs and the signal handler receives a structure
> that contains the file descriptor, so that we'd know which fd is affected
> without having to check every single one of them).
>
>
> The question is now: Has anyone any experience or thoughts as to how much
> such a single-threaded app will be slowed down by the large number of
> polls() necessary? As the server itself will need some serious CPU power to
> serve requests, it would be rather unfortunate if I found out that it spends
> 50% of its time just poll'ing  :-)
>
>
> Any thoughts on this matter highly welcome and appreciated (especially as I'm
> not really very deep into the matter).
>
> Many thanks in advance.
>
> Cheers
> -Tim
>
> PS: These are some pages are found that made me think about this issue, even
> if I don't _really_ understand half of it :-)
> http://www.kegel.com/c10k.html
> http://www.atnf.csiro.au/people/rgooch/linux/docs/io-events.html



-- 
      __          _    __ David Helder - dhelder umich edu
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