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AR# 45476

13.3 PlanAhead - Implementing a design using the 32-bit PlanAhead tool on a Windows 64-bit machine runs out of memory


If I run the PlanAhead tool in 32-bit mode (planAhead -m32) on a Windows 64-bit machine, an "Out of Memory" error occurs, even though the machine has more memory than is being used.

For example, the PlanAhead tool uses just over 1.6 GB during the route design, but my machine has 8 GB of memory. An error similar to the following occurs:

"Phase 3 Special Net Routing
Time (s): 150.043w. Memory (MB): 1639.266p 541.195g
Ending Routing Task
Time (s): 150.249w. Memory (MB): 1639.266p 541.195g
ERROR: The application has run out of memory while executing "route_design "
INFO: [PlanAhead-261] Exiting PlanAhead...
INFO: [Common-83] Releasing license: PlanAhead"


The PlanAhead 13.3 and earlier tool executables were compiled with the default memory setting. This results in a limitation of 2 GB for 32-bit executables running on Windows 64-bit operating systems. The 2 GB include heap, code, and stack. Due to the unreported overhead, it will appear that the application runs out of memory when using about 1.63 GB.

The PlanAhead 13.4 tool executables have been compiled with the IMAGE_FILE_LARGE_ADDRESS_AWARE set so that the available memory usage for an application is increased to 4 GB for 32-bite executables running on Windows 64-bit OS.

If more than 4 GB of memory is required, you should use the 64-bit PlanAhead tool.

AR# 45476
Date 11/07/2012
Status Archive
Type General Article
  • PlanAhead - 13.3