Memory Error

I am working with IntelliJ IDEA 2018.1.3 and running a Python code that dumps a large dictionary with the numpy package into a .npy file of size >100MB. When saving the file a Memory Error occurs. Files smaller than 100MB can still be saved, upon crossing 100MB saving produces a Memory Error. 

I tried increasing the Heap size of the JVM from -xms128m and -xmx750m to -xms 512m and -xmx2048 as stated in the links below, but still the error occurs. My task manager indicates that the Memory Error always occurs around 2.1GB RAM usage of IDEA. No matter the JVM settings, so I don´t know if it actually has an effect, although the CPU usage of IDEA now spikes to above 80% whereas before it was limited to around 30%.

Is there another setting from IDEA or even Windows producing the Memory Error?

https://intellij-support.jetbrains.com/hc/en-us/articles/206544869

https://stackoverflow.com/questions/28411803/outofmemoryerror-insufficient-memory-in-intellij#28411978