Change linebuffer arbiters to RRarbiters #640
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Related issue: N/A
Type of change: other enhancement
Impact: rtl refactoring
Development Phase: implementation
Release Notes
Changed the linebuffer arbiters in BoomMSHR to be RRArbiters which use round robin scheduling instead of arbiters, which use priority scheduling.
Note: This currently impacts performance by around ~10% (according to the read test with N=65536 in ucb-bar/chipyard#1478).
Benchmarking should be done to figure out what is causing the performance difference. Abe and Jerry's suggestion was to figure out the occupancy of each MSHR state in the RRArbiter implementation in comparison to the Arbiter implementation. Summary slides are linked here: https://docs.google.com/presentation/d/1E6beSmXTvA7i3Fidx7r5adM6YJHAKcfKDLTG5HufCzM/edit?usp=sharing