This page is intended for recording steps we have taken over time to improve RAMCloud performance, along with measurements of the resulting performance gains. Add new entries at the beginning of the page, so that the entries are in reverse chronological order.
Enqueue replication Rpcs from the service thread to dispatch thread instead of taking the Dispatch lock (December 2014, Henry Qin)
When servicing a Write Rpc, the service thread used to take the dispatch lock to block the dispatch thread from executing, and then proceed to use the transport to send the replication Rpc.
We have introduced the DispatchExec mechanism as a new Poller for the dispatch thread. The service thread will hand work to DispatchExec in lieu of taking the Dispatch Lock.
This optimization moves the median latency for writes from 14.4 us to 13.4 us.
Fetch multiple completions at once in InfRcTransport (August 2014, John Ousterhout)
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