Profile S2E's memory usage and identify what can be optimized

[humeafo]

I encountered a weird situation in S2E that with only two alive states but S2E consumed 20GB+ memory, there were some states killed this before, and some symbolic data introduced(say less than 30MB), I know there're some leaks such as klee's symbolic array etc, but should not consume this much, there must be some other big leak sources, how do you profile S2E's memory usage? Any advice on this?

[vitalych]

There are some hints here: http://s2e.systems/docs/src/ProfilingS2E.html

You could also recompile S2E with a malloc library that supports profiling. There should be a few out there.

30MB of symbolic data is huge btw. What are you trying to do?

[humeafo]

Thanks for the info. 30MB is accumulated size of many symbolic input data in many states, not a single input data in one state, all of the states (except one) were killed, but the memory consumption is still there.

[vitalych]

This is a very good issue, reopening it.

[vitalych]

Some ideas:

• Check how many memory pages are duplicated across states => could justify implementing deduplication
• Check heap fragmentation (could explain why memory usage doesn't seem to go down)
• Related issues: #92, #333, #341