Performance Metrics

From WhatsApp scalability talk

Slides
http://www.erlang-factory.com/upload/presentations/558/efsf2012-whatsapp-scaling.pdf
Talk
http://vimeo.com/44312354

  • pmcstat - processor hardware perf counters
  • dtrace
  • kernel lock-counting
  • gprof
  • fprof w/ & w/o cpu_timestamp
  • BEAM lock-counting (invaluable)

contention most significant issues

FreeBSD

backported TSC-based kernel timecounter
gettimofday(2) calls much less expensive

backported igp network driver
had issue with MSI-X queue stalls

syssctl tuning
obvious limits (e.g. kern.ipc.maxsokets)
net.inet.tcp.tcphashsize=524288


BEAM is erlangVM - lot of other info on that

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