Parallelize RAM Timestamp Count Initialization

[sragss]

For a 64 core machine at a cycle count of ~16M, Jolt spends ~3.5% of its time in a segment called memory_trace_processing here. This segment allocates and computes the offline memory checking (a,v,t) polynomials used for the combined registers and RAM. Some additional details can be found in the wiki.

Currently this ~300 line segment takes ~3.5% of end-to-end time because it is computed completely serially. No use of additional CPU cores. We should parallelize this to get up to a NUM_CPUx speedup.

The goal is to fill out the following.
Trace Length sized

• a_ram
• v_read
• v_write_rd
• v_write_ram
• t_read
• t_write_ram

Memory sized

• v_final
• t_final

It may be helpful to review the tracing strategy for performance testing.

[PatStiles]

Interested!

[moodlezoup]

done in #338