The microblog: 2022.06.15 09:50:47

2022.06.15 09:50:47 (1536979517117304832) from Daniel J. Bernstein, replying to "Gok (@Gok)" (1536967430798458880):

Most Intel and AMD chips at base frequency are way below thermal limits with good fans + server-room temperatures. ARM development boards tend to be harder to cool and often set their nominal frequencies too high; running the boards at lower frequencies helps them last longer.


2022.06.15 08:19:36 (1536956569220308992) from Daniel J. Bernstein:

Using all server cores _while keeping the hardware alive for a long time_ is what gets the most computation done per dollar. My experience running >100 servers of many different types is that the best clock frequencies for this are at or below base frequency, no Turbo Boost.

2022.06.15 08:31:48 (1536959642256957440) from "Gok (@Gok)":

Seems like this also requires you to pay for power to keep your server cores ticking even when doing little-to-nothing?

2022.06.15 08:57:44 (1536966169009106944) from Daniel J. Bernstein, replying to "Gok (@Gok)" (1536959642256957440):

1. Idle cores draw much less power even at full speed. 2. Almost all of my power consumption is for servers that I'm buying to get computations done (as opposed to Raspberry Pi etc for benchmarking). 3. The claim I'm disputing is about Turbo Boost, not about slow-down-when-idle.

2022.06.15 09:02:45 (1536967430798458880) from "Gok (@Gok)":

I suppose you also need to make sure you're not hitting any thermal throttling even without above-base boosting…