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To me we might need >> to go with reduced batch size of existing approach or multi level >> approach from Mathieu (I still have to see Mateusz and Kairui's >> proposals). > > Here is an initial userspace prototype of my hierarchical split counters: > > https://github.com/compudj/librseq/blob/percpu-counter/include/rseq/ > percpu-counter.h > https://github.com/compudj/librseq/blob/percpu-counter/src/percpu-counter.c > I've updated my branches to use unsigned long counters rather than signed. This eliminates tricky 32-bit/64-bit overflow corner-cases and should not have significant impact in practice. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com