Re: [Monotone-devel] Performance improvement splitout

[Alvaro Herrera]

Nathaniel Smith wrote:

> > 5cc1ed0346c5129ddd77ae895985bf743f349cae: skip calling select
> > Skip calling select again if we processed some data from the remote
> > side.  Somehow the call to select with a 1us timeout ends up waiting a
> > bunch of the time leading to idleness in the client (on a pull).
> > Oddly making this change significantly increases the amount of user
> > time; haven't investigated why as the tradeoff for reduced wall clock
> > time is a win.  Best guess is that because the client is running
> > faster, it makes more recv calls for less data.
> 
> Hmm, I don't get it -- if the socket is readable (and presumably it
> is, if we're getting bytes when we call recv), shouldn't select be
> returning instantly anyway?  Your description seems to indicate that
> it's actually blocking...

One syscall less maybe?

-- 
Alvaro Herrera                 http://www.amazon.com/gp/registry/DXLWNGRJD34J
Jajaja! Solo hablaba en serio!