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Dual CPU not sharing workload

DickDastardly
By DickDastardly
in Troubleshooting
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I want to start this with I hardly have any idea of what I'm doing so bear with me.

Bought an HP z840 with dual XEON 2680 v3 and 128gb ram. I'm running 10 instances of LDPlayer on the computer and everything is running great, however, i've noticed that CPU1 is doing the vast majority of the work (~60%) while CPU2 is chilling (~16%). I would assume that the work would be shared between the two? I'm not sure what information I need to provide so if more is needed please let me know.

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https://linustechtips.com/topic/1589725-dual-cpu-not-sharing-workload/
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Just curious; how much did you pay for this system? Specs look wild 😄

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Core usage may be like in series and first CPU isn't fully used yet

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The OS will tend to put the threads on the first cpu. 

 

There's higher latency when working on the second core and cache misses ... and it's higher latency when you have one thread exchanging data with a thread running on the other cpu. 

You could probably use CPU Affinity or other tools to lock instances of LDPlayer to a specific cpu, but probably your best bet would be to switch to a single CPU system. 

 

There's 48 core / 96 thread epyc processors for 300-350 dollars, motherboard's another 200$ or so. 

 

Here's a mobo + cpu bundle, for a 32 core / 64 thread epyc : https://www.ebay.com/itm/175323399510

Add another 50$ for the cooler, and you can probably reuse your current DDR4 if it's registered ecc ddr4. 

 

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Welcome to the forums!
Yeah, as others have stated, *most* software is unaware of multi CPU configs and just let the OS hand them threads and resources as they as ask for it. The OS knows that the 2nd CPU is not going to be as performant, so it offloads any workload that doesn't overly suffer from that latency (background tasks etc.) while keeping the stuff you're actually using on the primary CPU until it can't handle the load. 

Out of curiosity, what are you doing that needs 10 android emulators?

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