Threading Benchmarks, NetBSD versus FreeBSD

Andrew Doran posted some threading benchmark results to NetBSD's tech-kern mailing list, following up to some benchmarks he'd posted earlier. The results compared NetBSD -current with FreeBSD -current, and the Linux 2.6.21 kernel. Kris Kennaway was surprised by the results, and ran his own benchmarks with minimal configuration changes, summarizing, "this measurement shows that FreeBSD is performing 70-80% better than NetBSD in this 4 CPU configuration. This is in contrast to Andrew's findings which seem to show NetBSD performing 10% better than FreeBSD on a 4 CPU system (a very old one though)." He added, "the drop-off above 8 threads on FreeBSD is due to non-scalability of mysql itself. i.e. it comes from pthread mutex contention in userland."

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