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From sae...@ix.netcom.com
Subject Re: Memory Hog
Date Mon, 11 Oct 1999 02:31:07 GMT
Ryan, just a short comment about poll/select. The project that 
I was working on had a simple rule of portability. Use
poll() for TLI implementation and use select() for the 
BSD Socket implementations. This guaranteed maximum portability
among different Unixes.

Also there was a general agreement that BSD socket was more 
efficient than TLI because more performance work was done on
the BSD by the UC Berkely fellows than the TLI. So this makes
select() more efficient than poll(). We never measured the performance
of the two by profiling. It was just an agreement among the engineers.

   My two cents,
   ST.
  

Ryan Bloom wrote:
> 
> select is not more efficient that poll.  The current ap_poll when
> implemented using select is more efficient than the one implemented using
> poll.  That is a side-effect of what I was doing when I was coding it.  We
> NEED both implementations, because there are platforms that don't support
> select, or don't support it fully.  A good example of this, is BeOS, which
> doesn't pay attention to any of the select sets other than the read one.
> 
> The performance of the poll based ap_poll is not tragic.  It is also not
> unfixable.  There are ways to fix the performance af ap_pool when it uses
> poll.  Nobody has done them yet.
> 
> Ryan
> 
> On Sun, 10 Oct 1999, Manoj Kasichainula wrote:
> 
> > On Sun, Oct 10, 1999 at 02:24:46PM +0100, Ben Laurie wrote:
> > > Funnily enough, if poll() is emulated with select() the implementation
> > > is far more efficient.
> >
> > What was the purpose of poll() if select() is more efficient?
> >
> > --
> > Manoj Kasichainula - manojk at io dot com - http://www.io.com/~manojk/
> > "Life is like an analogy." - Aaron Allston
> >
> 
> _______________________________________________________________________
> Ryan Bloom              rbb@raleigh.ibm.com
> 4205 S Miami Blvd
> RTP, NC 27709           It's a beautiful sight to see good dancers
>                         doing simple steps.  It's a painful sight to
>                         see beginners doing complicated patterns.

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