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View new features for FlowTracer 2025.1.0.
FlowTracer Overview
An advanced mission critical dependency management platform for developing and executing flows.
FlowTracer Tutorials
Discover FlowTracer functionality with interactive tutorials.
Altair FlowTracer User Guide
FlowTracer is a complete system to create, manage, and execute design flows.
Altair FlowTracer Administrator Guide
This manual is aimed at the person who will be the administrator for FlowTracer. This person will be responsible for configuring the network resources, setting up the licensing, and establishing security and access rules for the system.
Altair FlowTracer Developer Guide
- FlowTracer Roles
  When using FlowTracer in large deployments, three main roles emerge: Administrator, Developer and User. In smaller organizations, a given person may have multiple roles, but the duties of each role still exist.
- Environment Management
  To ensure the correct and repeatable behavior of the tools, the environment must be controlled. This chapter explains how VOV supports multiple reusable environments.
- Execute Jobs From the Command Line
- Flowbuilding
  The trace is built using a combination of techniques.
- Flow Description Language (FDL)
- Tool Integration
  - Wrappers
  - Track the Origins of Dependencies
  - Integration by Interception
  - Library-based Interception
  - Integration by Instrumentation
  - VOV Instrumentation Library (VIL)
  - Instrumentation Procedure
  - VILtools
  - Integration by Encapsulation
  - Encapsulation Procedures
    In an encapsulation script, you can use the following Tcl procedures:
  - Capsule Post-Processing
  - Capsule On-the-Fly
  - Capsules for VHDL and Verilog Tools
- Integrate Difficult Tools
- Runtime Change Propagation Control
  The patented technique of Runtime Change Propagation Control (RCPC) provides the ability to stop the propagation of insignificant changes through the flow.
- Flow Library
  FlowTracer captures your design in design flows described by Flow.tcl files. The Flow Library is meant to help users locate and deploy instances of packaged flows bound to their specific design data.
- Files, Equivalences, Exclusions
  The files used in a project reside in one or more directories spread all around your filesystems. Each logical name defined in the equiv.tcl file implicitly declares the root of a workspace. You can browse the workspaces using the browser interface.
- Makefile Conversion
- Advanced Tasker Topics
- Resource Management
  The Resource Map Set represents the collection of resource maps that have been assigned to a project and the constraints associated with such resources.
- CGI Interface
- Events
  Every change in the trace is recorded as an event, which is then sent to all clients that subscribe to them.
- Miscellaneous

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Library-based Interception

This method is a technique where the system I/O library is replaced by a modified version that has been instrumented with FlowTracer. Without changing the source code of the tools, this technique is in fact a form of low-level instrumentation. The routines in the modified I/O library behave exactly as those in the original system library, except that a few additional calls to the VIL functions are made to declare the I/O behavior of the tool.

Because the runtime interception library is sensitive to all file I/O, it is most important to have a well-defined exclusion file to eliminate uninteresting files from the resulting trace. No other preparations are necessary.

To activate runtime interception, use the wrapper vrt or vw2. The command line options to vrt are similar to those of vw, and the method of invocation is the same:

% vrt cc -o prog src1.o src2.o src3.o

This technique is avalable for Linux.

Requirements for Linux

vrt only applies to executables linked with the dynamic C library. To find out if an executable qualifies, you can use the utilities file and ldd as in the following example:

% file /bin/ls
/bin/ls: ELF 32-bit MSB executable SPARC Version 1, dynamically linked, stripped