Performance

[ashwin153]

• Lower consensus backoff duration to slightly more than the 99% latency.
• Fail-fast if a proposal conflicts with a proposal on the same beaker.
• SortedMap to ConcurrentSkipListMap.
• Network and memory optimized EC2 instances.
• Increase JVM heap size to reduce GC pressure.
• EC2 Placement Groups to reduce latency.
• Do not perform consensus if there is only one beaker in the cluster.
• Allow prepare and learn to occur simultaneously.
• Executor look for latest conflicting transaction from right-to-left, not left-to-right.
• Return if a majority accept the proposal; don't wait for the proposal to be learned.

[ashwin153]

Note that YCSB benchmarks have to be run with higher operation counts, because the initialization of Beaker clients is expensive and will tend to dominate the runtime if the operation count is too low. This will result in lower than expected throughput.