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A comment on Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance on Debian Linux. Parent comment

Re:Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance... by sp332 on Friday April 13, 2018 @10:23AM (#16830254)
Offhand, I would guess that it's good for I/O-bound tasks, where you can have lots of threads waiting for input that don't need CPU time. A busy database maybe.
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Re:Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance... by lultimouomo on Friday April 13, 2018 @11:26AM (#16830861)
You don't need CPU threads for threads that don't need CPU...
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Re:Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance... by sp332 on Friday April 13, 2018 @11:41AM (#16831046)
The 8-core version only has 8 (each) ALUs, LSUs, and vector units. https://en.wikipedia.org/wiki/POWER9#Core If each core has 4 threads "running" on it, some of them are not going to be executing.
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Re:Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance... by Joky on Friday April 13, 2018 @12:02PM (#16831255)
Still: the kernel won’t schedule threads that are waiting on I/O i believe.
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Re:Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance... by sp332 on Friday April 13, 2018 @12:18PM (#16831421)
Ok that's an interesting point. So they'd have to be waiting on a fetch instruction for the time not to be totally wasted?
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Re:Power9 Benchmarks vs. Intel Xeon vs. AMD EPYC Performance... by blattimwind on Friday April 13, 2018 @01:13PM (#16831909)
Blocked tasks are not scheduled until unblocked.
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