hiccups with 0% cpu used (host) 0% speed in PCem
hiccups with 0% cpu used (host) 0% speed in PCem
One more observation of odd behavior.
PCem suddenly and repeatedly freezes for 3-5 seconds. The emulation freezes, not the emulator itself, whose window remains responsive.
This happens with very different machines.
When these freezes happen, PCem reports a "0%" of emulated cpu speed.
I expected a 100% cpu usage in task manager, where instead I can see the cpu usage quickly dropping to 0% and then going back to normal when PCem unfreezes.
Xeon W3960 (6 cores / 12 threads)
As usual I can provide configuration files etc. but so far it seems there isn't much interest in the oddities I keep stumbling on
PCem suddenly and repeatedly freezes for 3-5 seconds. The emulation freezes, not the emulator itself, whose window remains responsive.
This happens with very different machines.
When these freezes happen, PCem reports a "0%" of emulated cpu speed.
I expected a 100% cpu usage in task manager, where instead I can see the cpu usage quickly dropping to 0% and then going back to normal when PCem unfreezes.
Xeon W3960 (6 cores / 12 threads)
As usual I can provide configuration files etc. but so far it seems there isn't much interest in the oddities I keep stumbling on
- SarahWalker
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Re: hiccups with 0% cpu used (host) 0% speed in PCem
I'm very interested! Your other reported problems haven't been addressed yet due to a backlog of other things to look at, not due to a lack of interest!
Re: hiccups with 0% cpu used (host) 0% speed in PCem
Hah all right. I assumed that it wasn't the case due to using PCem on a not-so-common kind of hardware.
Configs attached, let me know if anything else is needed.
(I use shaders, which I didn't attach, but the problem happens with or without them, and with any of the renderers)
Moreover: at some point I thought dynarec was the culprit. I noticed the dynarec checkbox was greyed out. Changed cpu type, and saw now I could check/uncheck it. I unchecked it.
Later, when I switched back to the previous cpu, the dynarec checkbox became greyed out again - while still being unchecked. Expect behavior? Probably not.
Configs attached, let me know if anything else is needed.
(I use shaders, which I didn't attach, but the problem happens with or without them, and with any of the renderers)
Moreover: at some point I thought dynarec was the culprit. I noticed the dynarec checkbox was greyed out. Changed cpu type, and saw now I could check/uncheck it. I unchecked it.
Later, when I switched back to the previous cpu, the dynarec checkbox became greyed out again - while still being unchecked. Expect behavior? Probably not.
- Attachments
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- Pentium-100.cfg
- (1.48 KiB) Downloaded 330 times
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- 386-40.cfg
- (2.22 KiB) Downloaded 332 times
Re: hiccups with 0% cpu used (host) 0% speed in PCem
I have a spare i7 970 machine I can try it out tomorrow. What are the other specs of your machine?
Re: hiccups with 0% cpu used (host) 0% speed in PCem
This is expected behavior:resle wrote: ↑Mon 26 Feb, 2018 11:48 pmI noticed the dynarec checkbox was greyed out. Changed cpu type, and saw now I could check/uncheck it. I unchecked it.
Later, when I switched back to the previous cpu, the dynarec checkbox became greyed out again - while still being unchecked. Expect behavior? Probably not.
Dynamic grays out unchecked when you use any pre-486 CPU (including the "486" SLC/DLCs). No recompilers are implemented for those CPUs.
Dynamic grays out checked when you use any Pentium CPU or 6x86 CPU because having a C interpreter for those wouldn't be very effective to recreate their timing and how they batch instructions etc.
IDT Winchip allows interpreter emulation because it's a relatively simpler CPU meant as a low-power budget S7 CPU solution. Simpler than K5, K6, etc.
Re: hiccups with 0% cpu used (host) 0% speed in PCem
Xeon w3960 with ht enabled (12 logical cores)
Mb Asus rampage III
48gb ddr3
Geforce GTX980, latest drivers
Win 10x64 build 17107
3 x samsung 960pro ssd (os / swap / data)
Basically it's an 8 years old server/workstation with a few upgrades.
I doubt it matters but I have a couple Hyper-V machines running all the time in the background.
Thanks! Very informative. I wish there was detailed PCem documentation with this kind of stuff laid out for all the small bits and pieces, just as you did now...leilei wrote: ↑Tue 27 Feb, 2018 12:05 am This is expected behavior:
Dynamic grays out unchecked when you use any pre-486 CPU (including the "486" SLC/DLCs). No recompilers are implemented for those CPUs.
Dynamic grays out checked when you use any Pentium CPU or 6x86 CPU because having a C interpreter for those wouldn't be very effective to recreate their timing and how they batch instructions etc.
IDT Winchip allows interpreter emulation because it's a relatively simpler CPU meant as a low-power budget S7 CPU solution. Simpler than K5, K6, etc.
Re: hiccups with 0% cpu used (host) 0% speed in PCem
Are the hyper-v machines running when you use pcem? If so it will affect performance. Try running pcem with the hyper-v machines powered off.
Re: hiccups with 0% cpu used (host) 0% speed in PCem
I have 12 logical cores, the machines take about 10% of a core each. Keeping Chrome open uses more cpu than that.
Also as I mentioned, the problem is that pcem stops running for a few seconds, not that it slows down.
This is not a performance issue.
Re: hiccups with 0% cpu used (host) 0% speed in PCem
I ran it on my i7 970 which is the same socket as your pc 6 cores 12 threads and it ran just fine. I even played a game of warcraft to on an emulated pentium 120mhz.
Re: hiccups with 0% cpu used (host) 0% speed in PCem
as I said, this is not performance related.
I can emulate a Pentium MMX 233 mhz t 100% speed.
The hiccups happen both when I emulate a Pentium MMX233, a 386/40, or an 8088.
Re: hiccups with 0% cpu used (host) 0% speed in PCem
With the latest build of Windows 10 (17120), the problem is gone.