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Altair FlowTracer User Guide
FlowTracer is a complete system to create, manage, and execute design flows.
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Unexpected Dependency Graph

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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.
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Discover FlowTracer functionality with interactive tutorials.
Altair FlowTracer User Guide
FlowTracer is a complete system to create, manage, and execute design flows.
- 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.
- Introduction to VOV
  FlowTracer is derived from the system "VOV" originally developed at UC-Berkeley. The word "VOV" is not an acronym, but can be thought of as a contraction of the word "evolve".
- Concepts and Terminology
- Run, Rerun, Stop and Kill Jobs
  The act of requesting FlowTracer to bring a particular target up-to-date is sometimes called a Retrace Request or more simply a Retrace.
- Find, Remove and Clean Files
- Graphical User Interface
- Browser Interface
  This chapter will cover how you can use your web browser to manage FlowTracer.
- Command Line Interface
  The Altair Accelerator products have a rich set of programs that can be run on the shell command line.
- Create Sets with Selection Rules
- Advanced Information
  - Tasker Compatibility
    When a job becomes eligible to run, VOV places it on the fastest vovtasker host which offers all the resources requested when the job was submitted. The Tasker Compatibility page in the web browser UI shows details of a job's compatibility with each vovtasker machine. You can use this page to understand why a job seems stuck.
  - Unexpected Dependency Graph
- Troubleshooting
- Create a FlowTracer Project
- Resource Management
  Altair Accelerator includes a subsystem for managing computing resources. This allows the design team to factor in various constraints regarding hardware and software resources, as well as site policy constraints.
- Rename Nodes
  Renaming of nodes is a task for more advanced users. In most cases, it is simpler to forget all nodes and rebuild the trace from scratch.
- Miscellaneous
- Reports
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

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Unexpected Dependency Graph

Check File System Synchronization

A common problem with many networks becomes apparent to users only when FlowTracer is deployed, which makes it appear like a "FlowTracer problem" when it is not. The problem is a possible lack of synchronization between the clocks of the computers in your network. FlowTracer will not schedule and deploy jobs as expected if timestamps are not consistent, because the server host and the file system host have timestamps that are out of sync. Test this synchronization with the following command:

% vovguru -T . # Do not forget the dot "."
vovguru Oct 19 17:57:18 Filesystem . seems OK (deltaT=0)

If you get a response like the one shown above, with deltaT=0, you are OK.

If deltaT is not 0, you have a synchronization problem. Solve this problem in the following ways:

Change host so that you are using the same machine for the FlowTracer server and the file server.
Ask your system admin to keep the network clocks synchronized.