New Memory bug

DustinHullett

DustinHullett

Product Expert
just want to post here for the dev team. I think i have found another Bug in Parallels Desktop 12.0.2 for mac. The memory usage for my Windows 7 pro x64 VM in activity monitor stays around 2 - 4 when im doing normal taks and the machine is running regularly. But if i suspend the VM whenever i take it back active the memory is maxed out all the time at whatever the max allocation is in my settings. I have tested this with changing my allocated memory from 4 to 8 GB and after suspending the VM it alwayse goes to the max. Therefor i have to restart the VM to release the memory if not it starts slowing down everything.
 
I wonder if this is the same as something I'm seeing. I am running Windows 7 Pro via Parallels 12 and El Capitan 10.11.6 on an iMac with 8Gb of memory, with 2.3Gb given to Parallels. In fact I just upgraded to Parallels Desktop 12 from 11. I'm seeing maxed out CPU time on the Mac's Activity Monitor (99 to 102 percent all the time), even when there are supposedly no programs running in Windows (and very little running on the Mac). Parallels' own monitor suggests it's using 25-50 percent CPU and an unchanging 36% RAM - don't know which to believe. When I do run a program in Window 7, just launching programs can take around a minute in some cases. Once the program is in memory it seems pretty responsive. This happened pretty much with Parallels 11, only the performance was more sluggish. Is this a bug, or is there some parameter one can tweak? BTW I'm running a second monitor, but Parallels/VM isn't using it - I notice some forum posts that suggest that the second monitor has some influence on performance.
 
Just a comment on the above, that KB article 122774 (disable wmpbetwk.exe) did help some, but I am still getting a lot of 100% readings on the Mac Activity Monitor for Windows 7. I will write to support.
 
How many CPU cores do you have allocated to your VM? Also on a Mac 100% means 100% of one core not total CPU useage. So if you have 8 logical cores 800% in activity monitor will be maxed out cpu
 
Apparently this machine (I mean the iMac) has four cores. In the Actions/Configure menu for W7 it says I've got one processor - does this mean the VM is using only one core (I have never had to consider this issue before, so I'm a bit confused)? Anyway I think what you're saying is that 400% would be maxed out on my machine, so 100% is actually only 25% of the available CPU power, which is nearer to what the CPU/RAM usage window on Parallels itself says. OTOH, why should an idle system use more than a tiny fraction of the available CPU power - I realise there are background activities, but judging by the Mac, these should be consuming a trivial amount of CPU, closer to 1% than 25%. Sorry to be so dumb.
 
Yes this is correct. But you are right an idle system should only use 5 to 15% of one core. See what's using CPU in your task manager in Windows. Open up task manager and click on the services tab and then click CPU to sort by what is using the most CPU. This should give you the service name that's causing problems. I will warn you leaving windows update turned on uses a lot of resources and will be under netsrvcs. I always get the updates I want then turn it off.
 
On my machine with 4 cores allocated to the VM windows update on automatic will always use 22 to 33% CPU. Which shows anywhere from 100 to 200 sometimes in activity monitor.
 
Thanks so much for staying with me. You were right - the ONLY significant user of resources when the VM isn't supposed to be running a user-level program is svchost.exe (netsvcs). I have no idea how to stop it running, sadly, as I am basically a Mac guy who needs a PC (or a VM) to test cross-platform software. I find it odd that Parallels themselves don't give more tips on this; or perhaps they do and I just missed them.
 
Just to say I found out how to turn the updater off... will have a look soon to see if performance has improved.
 
Thanks so much, that really worked (sorry for the delay in replying). The Parallels resource usage meter for Windows 7 now remains at about 1% (with short higher peaks) when the OS is idle - this is obviously acceptable. I note that the Mac's Activity Monitor does give W7 a higher percentage (around 5% with higher peaks). Not sure what this means - no doubt I am not really comparing like with like.
I had a support query out to Parallels. They responded with a suggestion that they had a real-time look at my VM, but after your advice I declined.

Thanks again
 
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