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From: Jennifer Finlinson <jennifer@lineo.com>
Subject: Technical Information from Lineo on Linux Trace Toolkit
Date: Wed, 30 Aug 2000 9:48:00
To: corbet@eklektix.com


Linux Trace Toolkit for RealTime 
"Analysis and Display of System Level Events" 

Technical Bulletin
Aug. 30, 2000 -- Montreal, Canada / Lindon, UT -- Today, Opersys, Inc
and Lineo, Inc announced the availability of the Linux Trace Toolkit (LTT)
for Real-Time Linux.  Although LTT has been available for standard Linux
user-space tasks for many months, it has only now been modified to provide
the capability to trace real-time Linux tasks running in the kernel memory
space. 
Like the expensive time-tracing solutions available for many proprietary
embedded RTOS solutions, LTT provides developers with all of the information
necessary to reconstruct a system's behavior over a certain period of
time. Using LTT, one can graphically view the precise dynamics of a system,
answering such questions as: 
**Who actually has access to the hardware during a specific time slice?
**What happens to an application when it receives data?
**Where are the I/O latencies in a given application?
**When is a specific application actually reading from disk?
**Why do certain synchronization problems occur?

LTT provides this related information through three primary graphical
and text information displays which map the system's lowest level processes
(such as scheduling decisions, process switches and various management
tasks) to each high-level application -- all plotted against the time
axis. 
The event graph provides the viewer with a unique perspective on the flow
of events in the system. Every control modifying event changes the appearance
of the graph. 
The process analysis thumbnail provides the user with an in-depth analysis
of every process that existed during the course of the trace. The items
displayed are the same for all the processes except process 0 (idle) which
is called 'The All Mighty' and is used to display the summarized information
about the whole system. 
The raw list of events is, as its name says, the raw list of events that
occurred during the period of the trace. All the events are listed with
the exact time at which they occurred, the PID of the process to which
they belonged, the amount of space occupied by the event in the trace
module in the kernel and the string accompanying the event, if any.
Availability: 
LTT is an open source project that is freely distributable under the GNU
General Public License.  Additional information and a download for LTT
is provided from the Opersys LTT project page at: http://www.opersys.com/LTT/
 This work has been performed by Karim Yaghmour (karym@opersys.com) -
the chief architect of LTT and founder of Opersys, Inc. under funding
by Lineo, Inc. 
A pre-patched version of LTT as well as other real-time Linux debug tools
will be available in Q4 on Lineo's Embedix RealTime CD now undergoing
beta testing. Watch forthcoming news releases for details. 
About Lineo, Inc. 
Lineo, Inc. is a leading innovator of Linux-based embedded, real-time
and high availability system software, applications, hardware designs
and professional services. Lineo provides OEMs with software and hardware
solutions for creating devices and systems that interact with the Internet
while reducing system requirements and per-unit costs. Lineo's key product
lines include: Embedix (embedded Linux system software), uClinux (embedded
Linux for MMU-less processors), NETtel (Linux-based routers for secure
networking) and High Availability Cluster (mission critical Linux cluster
solutions).  Contact Lineo at www.lineo.com, via e-mail to info@lineo.com
or by calling (801) 426-5001. 
About Opersys, Inc. 
Opersys, Inc. was founded in 1999. Its primary goal is to provide expertise
in the often obscure world of operating systems.  This expertise strongly
encourages the usage of solutions based on the Linux kernel and it's real-time
derivatives.  Opersys is based in Montreal, Canada. Our staff is composed
of open-source enthusiasts who have a keen sense of designing, coding,
teaching and learning.  Contact Opersys at http://www.opersys.com, or
via e-mail at info@opersys.com.