Re: Mach, a but choise ?

[Patrick Strasser <pstrasser@gmx.net>]

Neal H Walfield wrote:
 
> I do not think removing a few functions would make any kind of
> difference -- if they are that slow avoid using them. 

It would be a lot of work and break the interface/compatibility with
other flavours of Mach, if that is a reason for the project.
But OTOH it would ease maintenance. Is actually anyone workong at
gnumach (not only patching)?

> The reason the L4
> people claim that Mach is so slow is that it uses async ipc messages.
> What does that mean?  I send a message to you.  Inside the message, I
> send a reply port.  After I send the message, I wait on the reply port
> until you send me the result.  In L4 they have (only) synchronous
> messages based on your tid (thread id) so when you send a message, it
> is ``easier'' to optimize.

I remember of reading of neither the Hurd nor gnumach being profiled at
all.
Could this be a reason of this legendary inefficiency of the Hurd? 

Patrick