Memory limit in enclave manifest and EPC paging performance

[Rafal_W_]

Hello, Is there a documented upper memory (heap) limit (HeapMaxSize in enclave config)? From testing it seems that the sign tool rejects values above around 0xfffcff000. I guess 64GB should be enough for everybody ;) On a similar topic, are there any tips for optimizing large memory accesses in enclaves? From my testing it seems that random memory access times drop 100-500x when EPC swapping is involved, compared to cases when all needed enclave memory fits in the EPC. Is there anything that can be done to improve enclave memory access performance when linear access is not an option and accesses cause EPC swapping?

[Hoang_N_Intel]

Complete SGX source code including memory management is available at https://01.org/intel-software-guard-extensions/downloads/source-code-repositories for your analysis.

In addition, there is also a white paper on SGX performance considerations including EPC and memory usage at https://software.intel.com/sites/default/files/managed/09/37/Intel-SGX-Performance-Considerations.pdf that may be of your interest.