Large Scale DSO for Parametric Analysis

Large Scale DSO for parametric analysis operates through a non-graphical batch application called desktopjob. You can run the desktopjob command-line to perform parametric analysis DSO. The command-line interface supported by this batch program is similar to the command-line used for regular DSO jobs.

Large Scale DSO is used for 'large scale parallel' jobs, which either fail or scale poorly as Regular DSO jobs. A Large Scale DSO job does not support the output of full parametric results, but produces “reduced” datasets corresponding to predefined Rectangular plots. The extracted columns of data are saved as .csv files. Typically, there is one .csv file per-trace, per-variation. These .csv outputs can be used directly in downstream applications (for example, Excel, or custom programs that parse .csv files). They can also be Imported as Dataset Solutions for post processing. Non-Rectangular plots of the design (such as statistical eye or digital plot) are not extracted). In order to produce a new output you must re-run the analysis.

The basic process involves these steps:

Prepare the project for Large Scale DSO Analysis
Submit the Large Scale DSO Job through the Tools > Job Management menu, or via a command line.
Monitor the job’s progress
Post process the results

For details, refer to the following sections:

Large Scale Distributed Solve Operation could submit a parametric setup to be solved in multiple machines, each machine may launch multiple EM-Desktop processes to solve the assigned variations (Design Points). Variations are distributed to each task (EM-Desktop process) equally, regardless of the machine hardware and each variation’s complexity. In practice, some tasks may finish earlier than others, in some extreme case some tasks may hours behind fastest task. DSO can redistribute tasks when a task finishes before other task. Variations are removed from slow tasks and reassigned to fast tasks. If you abort a task, they can be re-assigned to the running task, when the running task finish its original assignment. For more information, see Large Scale DSO theory.

Large Scale DSO offers two new batchoptions related to the redistribution ability:

LargeScaleDSO/VarRedistribution, where 0 disables redistribution (default), and 1 enables it.
LargeScaleDSO/RedistributionLimit, is a positive integer specifying the minimum estimated remaining time (in minutes) for variations to redistribute to another task. The default is 3.

Aborting a Large Scale DSO Simulation

To abort the whole Job, select the Abort button in the Job Monitor dialog box.

To abort using the Job progress bar, click the button next to the Job progress bar, Click the Abort menu item in the window.

To abort all tasks in a Node(host), click the button next to the node progress bar., and click the Abort menu item in the window. Aborted Variations will be redistributed to other running Nodes, if redistribution is turned on.

To abort an individual task, click the button next to the node progress bar, and click the “Detail” menu item in the window. In the Task status dialog box, click the Task button in the grid. In the variation status dialog box, click the Abort button. Aborted Variations will be redistributed to other running tasks, if redistribution is turned on.

To terminate a hanging EM-Desktop process, the hanging ansysedt.exe process won’t respond to the first abort command. Send a second abort command to terminate the hanging process. Remaining variations will be redistributed to other running tasks, if redistribution is turned on.

For an EM-Desktop process crashed or killed by Windows Task manager or other tools, the task status will be shown as aborted, Remaining variations will be redistributed to other running tasks, if redistribution is turned on.

Large Scale DSO for Parametric Analysis

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