Quotes tagged ‘Performance Tuning’

(2 total)

Stalled means the processor was not making forward progress with instructions, and usually happens because it is waiting on memory I/O. The ratio I drew above (between busy and stalled) is what I typically see in production. Chances are, you're mostly stalled, but don't know it.

— Brendan Gregg, brendangregg.com

You can additionally reduce latency by applying CPU affinity on each thread/process, e.g. nginx has worker_cpu_affinity directive, that can automatically bind each web server process to its own core. This should eliminate CPU migrations, reduce cache misses and pagefaults, and slightly increase inst…

— Alexey Ivanov, blogs.dropbox.com




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