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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
OS Components & Operations
System Analysis Toolkit (SAT) User's Guide
Interpreting Trace Data
Once the data has been captured, you may process it, either in real time or offline.
Building your own parser
Event interlacing
Although events are timestamped immediately, they may not be written to the buffer in a single operation (atomically). When multiple buffer slot events (combine events) are being written to the buffer, the process is frequently interrupted to allow other threads and processes to run. Events triggered by higher-priority threads are often written to the buffer first. Thus, events may be interlaced.

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
- Quickstart Guide
- System Architecture
  The System Architecture guide accompanies the QNX OS and is intended for both application developers and end-users.
- OS Components & Operations
  - Boot Optimization Guide
    The Boot Optimization Guide describes techniques you can use to reduce the time from your board's initial power on until you have a fully functional QNX system running on the board.
  - Building Embedded Systems
    The Building Embedded Systems guide is intended for developers who are developing or building BSPs for QNX OS embedded systems.
  - Customizing a BSP
    While QNX provides Board Support Packages (BSPs) for many common platforms and their individual variants, in some cases, you need a BSP for a board that QNX does not provide. If this is the case, you can modify a QNX BSP or develop your own.
  - Device Publishers Developer's Guide
  - High Availability Framework Developer's Guide
  - High-Performance Networking Stack (io-sock) User's Guide
    This guide contains instructions for implementing and using the QNX OS High-Performance Networking Stack and its manager, io-sock.
  - PCI Server User's Guide
  - Performance Tuning User's Guide
  - SMMUMAN User's Guide
  - System Analysis Toolkit (SAT) User's Guide
    - Introduction to the System Analysis Toolkit (SAT)
    - Events and the Kernel
    - Kernel Buffer Management
      As the instrumented kernel intercepts events, it stores them in a ring of buffers.
    - Capturing Trace Data
    - Filtering
    - Interpreting Trace Data
      Once the data has been captured, you may process it, either in real time or offline.
      - Using traceprinter and interpreting the output
      - Building your own parser
        The traceparser library
        The traceparser library provides a front end to facilitate the handling and parsing of events received from the instrumented kernel and the data-capture utility.
        Simple and combine events, event buffer slots, and the traceevent_t structure
        A simple event is an event that can be described in a single event buffer slot; a combine event is an event that's larger and can be fully described only in multiple event buffer slots. Both simple and combine events consist of only one kernel event.
        Event interlacing
        Although events are timestamped immediately, they may not be written to the buffer in a single operation (atomically). When multiple buffer slot events (combine events) are being written to the buffer, the process is frequently interrupted to allow other threads and processes to run. Events triggered by higher-priority threads are often written to the buffer first. Thus, events may be interlaced.
        Timestamps
        The timestamp is the 32 Least Significant Bits (LSB) part of the 64-bit clock.
    - Tutorials: Controlling event tracing
    - Current Trace Events and Data
  - Technotes
  - User's Guide
    The QNX OS User's Guide is intended for all users of a QNX OS system, from system administrators to end users.
- Graphics
- Programming
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX OS system and developers who want to create a QNX OS resource manager free from vulnerabilities.
- Utilities & Libraries
- Migrating to QNX OS 8.0
QNX Software in the Cloud
QNX Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

Event interlacing

QNX SDP8.0System Analysis Toolkit (SAT) User's GuideUser

Although events are timestamped immediately, they may not be written to the buffer in a single operation (atomically). When multiple buffer slot events (combine events) are being written to the buffer, the process is frequently interrupted to allow other threads and processes to run. Events triggered by higher-priority threads are often written to the buffer first. Thus, events may be interlaced.

Although events may not be contiguous, they are not scrambled (unless there's a buffer overrun). The sequential order of the combine event is always correct, even if it's interrupted with a different event.

To maintain speed during runtime, the instrumented kernel writes events unsorted as quickly as possible; reassembling the combine events must be done in post-processing. The libtraceparser API transparently reassembles the events.

Page updated: August 09, 2024