Unparking Cores, Potential CPU Performance Gain in Windows 7 (AMD FX Series)

I was messing around with some settings and doing some final research on my FX 4100 processor (upgrading to a i7 4790k and new motherboard for Christmas), and discovered core parking within Windows 7 and how to unpark them with a simple registry edit as a solution. For whatever reason, this had quite an effect on my performance in BeamNG. I went from awful stutter during collisions and occasional sub-20 FPS with input lag on all but the least complex vehicles and maps, to minimal stuttering during collisions and maintaining a 30-50 FPS range with the Bolide and Grand Marshal (and anything less complex) on the Industrial Circuit, and a fairly playable steady FPS of 25 with the Moonhawk. It's not amazing, but it's definitely the difference between the game being playable and being mostly unplayable. The thing is, this difference doesn't seem to show up in Banana Bench at all. It's only the performance during actual gameplay that seems to have improved significantly, as well as parking no longer appearing in the resource monitor. I haven't checked to see if this resulted in performance gains in any other CPU-heavy game or application yet, but I could check before I upgrade my PC if it'd be helpful.

If you're unsure if your cores are being parked, go into the Resource Monitor and check the CPU tab. Your minimally used cores should say they're being parked if Windows 7 is doing so. If anyone wants to try unparking their cores, I followed the instructions in red here: http://forum.cakewalk.com/tm.aspx?m=1861804. As with any registry edits, it'd probably be a good idea to back up your computer first before editing anything. However, I just went into regedit and did it immediately because I'm going to be doing a clean install for my new Christmas hardware anyways, and it worked with no issues.

So, has anyone else unparked their CPU, especially anyone with Bulldozer-based CPUs, and had similar results? Does this have any benefits for other types of quad core or more processors?

 

I just unparked cores on my hyper-threaded dual-core (4 threads, which looks like 4 cores to the OS) i3-4130. I noticed some improvement, but it was okay at the beginning anyway.

 

One thing to note, parked cores are effectively in a power saving mode and consuming negligible power. Disable parking and you effectively reduce the ability for a single core to be power saving, they can still clock up and down to save power but not fully disable. I think that is the only major downside and shouldnt be notable at all in a desktop but may be somewhat detrimental to laptop battery lives (although alot of laptops are still duals and likely arent parking very often).

It does apparently fix the retail copies of SimCity 4 (steam and origin versions apparently dont suffer from this issue) crashing on multicore systems though, but I used to just use -cpucount=1 instead