IBM Support

Merging two large streams results in 100% CPU utilization

Technote (troubleshooting)


Attempts to merge two large streams results in 100% CPU utilization with the eclipse client and long duration for the task to complete with IBM Rational Team Concert.


When merging two large streams (each stream with 15,000 files or more), the process duration takes a long time and results in the eclipse client machine at 100% CPU utilization.


Merging two streams is a time and processor consuming operation.

Resolving the problem

Merging two big streams is a time consuming operation by design. However, there are several ways to make this operation faster:

  • Reduce number of changes in files to merge,

  • Increase -Xmx value in eclipse.ini file,

  • Disable the "Build Automatically" option in RTC client, by following the steps below:

    1. Navigate to menu Window -> Preferences,

    2. Navigate to General -> Workspace,


    4. Uncheck the "Build automatically" option.

Leverage the Jazz Community

Jazz and Rational Team Concert have an active community that can provide you with additional resources. Browse and contribute to the User forums, contribute to the Team Blog and review the Team wiki.
Refer to technote 1319600 for details and links.

Document information

More support for: Rational Team Concert

Software version: 3.0

Operating system(s): Linux, Windows

Software edition: Enterprise, Express, Express-C, Standard

Reference #: 1501871

Modified date: 11 December 2012