lkml.org 
[lkml]   [2000]   [Jul]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: a joint letter on low latency and Linux
Out of all the jitter on this subject there is some excellent news:

- A 2.4 preemption point patch will get produced by Ingo (note: I'm
no fan of preemption points! But sometimes an ugly solution is better
than no solution).

- 2.5 will move to the "right" (imo) solution, namely, a preemptible
kernel leveraging the SMP capabilities of Linux. This is fantastic
news, and should address the core need stated in the open letter (albeit
not in 2.4).

I believe that under many important environments, such a system can
actually have better throughput than a non-preemptible kernel based
system (in contrast to those who believe responsiveness and throughput
are fundamentally at odds in OS design).

MontaVista is working to measure the preemption delays in a prototype
uniprocessor preemptible Linux kernel. We'll share results when we have
them. If anyone else is working on this we'd be interested in
collaboration.

As for all the debate around when and where and how RTLinux/RTAI
solutions should be used...from a vendor's perspective, the customer is
usually right, and our customers are requiring both RTLinux product from
us, and "native Linux responsiveness" ala Ingo patches as product from
us (usually not both from the same customer). We just explain the
hows/whats/pros/cons of each and let them decide how to architect their
solutions.

Long term, imo, "standard" Linux must have better user level process
responsiveness under load to become a truly ubiquitus operating
environment for modern desktops, servers and devices. Sounds like 2.5
and beyond should meet the need for the most part, and that's very
encouraging.


-Kevin


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:57    [W:0.029 / U:0.692 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site