Limit memory consumption of sensitivity analysis

[geofjamg]

• Do you want to request a feature or report a bug?
  Feature

• What is the current behavior?
  For both AC and DC sensitivity analysis, all factors end up in a "factor state" dense matrix. We already encountered 2 issues:

  • it sometimes can be greater that Java array size limit (which is the size of an integer)
  • it could lead a very high and uncontrollable memory consumption

• What is the expected behavior?
  We should be able to configure a "chunk size" so that internally DC and AC sensitivity analysis process factors by batches and so on limit the memory consumption even if lower performance.

• What is the motivation / use case for changing the behavior?
  Control memory consumption and allows to process a higher number of factors.

• Please tell us about your environment:

  • PowSyBl Version: ...
  • OS Version: ...

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, spectrum, etc)

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