[p2-dev] memory usage of SAT4J

[Mengxin Zhu <kane.zhu@xxxxxxxxxxxxx>]

Hi Daniel and Pascal,

I observed SAT4J library need lots of memory for resolving dependencies.

In our case we want to install 677 root IUs, and there are totally 17000 
IUs in multiple repositories. More than 240M memory was used in 
resolving process. Especially SAT4J library totally created more than 
210M int[] instances, and held them until the calculating completed. 
Above memory usage data is obtained in VisualVM.

Is it expected behavior to create and hold such large int array for 
calculating the dependencies? If it's unavoidable trade-off for the 
calculating, do we have a formula to estimate how much memory will be 
required when resolving dependencies in certain number of IUs?

Thank you in advance,
Cheers,
  Mengxin Zhu