[FeedSim] Keep number of driver threads and thrift threads in balance with SMT#567
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lukalt wants to merge 1 commit into
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[FeedSim] Keep number of driver threads and thrift threads in balance with SMT#567lukalt wants to merge 1 commit into
lukalt wants to merge 1 commit into
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To achieve optimal performance for FeedSim, the number of driver connections and thrift threads should be always kept in balance. Every driver thread uses 4 connections of the thrift server, so we need to ensure that
#driver_threads * 4 = #thrift_threads.#driver_threads = #thrift_threads/4)./sys/devices/system/cpu/smt/active),#driver_threads = #thrift_threads/5is used. So, the number of driver connections is only 80% of the number of thrift threads. Consequently, the driver does not spawn enough threads and only 80% of the thrift threads are busy.This PR fixes this discrepancy by using the same formula to compute the number of driver threads on systems with and without SMT. This improves performance by up to 20%.