Re: [patch 00/13] Syslets, "Threadlets", generic AIO support, v3

From: Evgeniy Polyakov
Date: Fri Mar 02 2007 - 03:13:58 EST


On Thu, Mar 01, 2007 at 11:31:14AM -0800, Davide Libenzi (davidel@xxxxxxxxxxxxxxx) wrote:
> On Thu, 1 Mar 2007, Evgeniy Polyakov wrote:
>
> > Ingo, do you really think I will send mails with faked benchmarks? :))
>
> I don't think he ever implied that. He was only suggesting that when you
> post benchmarks, and even more when you make claims based on benchmarks,
> you need to be extra carefull about what you measure. Otherwise the
> external view that you give to others does not look good.
> Kevent can be really faster than epoll, but if you post broken benchmarks
> (that can be, unrealiable HTTP loaders, broken server implemenations,
> etc..) and make claims based on that, the only effect that you have is to
> lose your point.

We seems to move far away from original topic - I never built any
assumptions on top of kevent _performance_ - kevent is a logical
extrapolation of the epoll, I only showed that event driven model can be
fast and it outperforms threadlet one - after we changed topic we were
unable to actually test threadlets in networking environment, since the
only test I ran showed that threadlest do not reschedule at all, and
Ingo's tests showed small number of reschedulings.

So, I only talked that kevent is superior compared to epoll because (and
it is _main_ issue) of its ability to handle essentially any kind of
events with very small overhead (the same as epoll has in struct file -
list and spinlock) and without significant price of struct file binding
to event.

I did not want and do not want to hurt anyone (even Ingo, although he is
against kevent :), but my opinion is that thread moved from nice
discussion about threads and events with jokes and fun into quite angry
word throwings, and that is too good - let's make it fun again.
I'm not a native english speaker (and do not use a dictionary), so it is
quite possible that some my phrases were not exactly nice, but it was
unintentional (at least not very) :)

Peace?

> - Davide
>

--
Evgeniy Polyakov
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