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Havoc ◴[] No.42752917[source]
I still don’t quite get how the cpu knows what is low priority or background. Or is that steered at OS level a bit like cpu pinning ?
replies(2): >>42752924 #>>42753121 #
tredre3 ◴[] No.42753121[source]
When the P/E model was introduced by Intel, there was a fairly long transition period where both Windows and Linux performed unpredictably poorly for most compute-intensive work loads, to the point where the advice was to disable the E cores entirely if you were gaming or doing anything remotely CPU-intensive or if your OS was never going to be updated (Win 7/8, many LTS Linux).

It's not entirely clear to me why it took a while to add support on Linux because the kernel already supported big.LITTLE and from the scheduler's point of view it's the same thing as Intel's P/E cores. I guess the patch must've been simple but it just took very long to trickle down to common distributions?

replies(1): >>42753714 #
1. baobun ◴[] No.42753714[source]
Not very surprisingly but IME running VMs you still want to pin (at least on Linux).