High CPU usage on disk access since update to Mojave 10.14.4 ?

Folks at VMWare have been reporting a similar issue since the update to 10.14.4 due to a bug Apple introduced in handling large files, have a look at the following link for more details:
https://planetvm.net/blog/?p=67185

It's been reported as officially solved by VMWare with Apple's macOS 10.14.6 supplemental update.

It remains to been seen if the same applies to Parallels as they haven't been forthcoming about this issue in any shape or form (as far as I know). In other posts, some users claimed that the 10.14.6 supplemental update fixes the issue. Others have reported that macOS Catalina 10.15 still have the issue so I'm still inclined to stay with Parallels Desktop 14.1.3 on macOS 10.14.3 for the time being.

I'm thinking of moving to VMWare Fusion, I might not like the UI and integration as much as Parallels but at least they seem to know what's going on with their product and even though they didn't know the solution at first, they were transparent about it. Wish I could say the same for Parallels but it feels more like a case of "you're holding it wrong" to me.

Any brave souls willing to try the 10.14.6 supplemental update and let us know how it goes with a large VM?

 

@PatrickC11 I've been using the very latest PD 15.1.0 (47107) on latest Catalina 10.15 (19A602) with a 430 GB VM running Win10 and it seems fine. Any major performance / stuttering issues I've had in the past were fixed by switching to the Apple Hypervisor and occasionally cloning my VM and switching to the clone.

My primary workload is C++ software development and my compiles generate around 50 GB of output, so it puts some strain on the parallels storage path. When I use the Parallels hypervisor I was still getting pauses and poor performance during disk I/O, but I haven't tested again since Catalina came out.

 

Oh. my. goodness. I do Windows development exploitation Visual Studio on Parallels on my MacBook professional and currently, I am fully stuck. I do not have a machine to roll back to. What are my options? The Activity monitor shows Windows ten professional at four-hundredth. I waited a handful of hours and let the machine fan whir and spin and currently, it's like it's coming back to traditional. I did not get to modify any settings or something. If I had to guess, it appears like there was a method doing a little quite disk improvement or conversion and once it got done, it's fine.

I'm crossing my fingers that it's attending to work ok within the approaching hours, days, etc.

 

I've tested Mojave 10.14.3 (HFS+) and a fresh install of 10.14.3 (APFS) with no performance problem. Every later OS has a performance problem - I've tested fresh installs of 10.14.4, 10.14.5, 10.14.6, 10.15 (all APFS). So something must have changed with 10.14.4. There is no Apple/Parallels hypervisor option on my MacPro3,1. Apple has not released the kernel source code for 10.14.4 yet so I can't tell what changed there.

 

I've tested VMs with < 4GB of RAM and ≥ 32 GB of RAM. No change.

 

I have a different VM using a Boot Camp HD. It's Windows 7 32 bit. I've allocated 1732 MB of RAM. I measured the time it takes to startup (until Windows desktop is reached and CPU is idle) and the time it takes to shutdown:
macOS 10.14.3: startup: 36 seconds; shutdown: 13 seconds
macOS 10.15: startup: 333 seconds; shutdown: 218 seconds

 

The VMWare thread talks about a performance issue with 10.14.6 caused by a problem in the vfs_drt_alloc_map function in the kernel that affects mostly VMs that use encryption. There are some facts that make me think that is a different problem than what we are experiencing (or at least I am experiencing).
1) They don't mention 10.14.4 or 10.14.5.
2) The VMWare thread says their problem is fixed in the latest 10.14.6 but the Parallels problem still exists.
3) My VMs are not encrypted.
4) I've compared the disassembly of the vfs_drt_alloc_map function between 10.14.3, 10.14.4, and 10.14.5 and found no significant differences. 10.14.6 does seem to have the new 32GB case that is mentioned in the VMWare post. I did not check if the mentioned bug exists in the disassembly, and I did not compare with an earlier 10.14.6 (without the supplemental update).

 

I installed Parallels 15 today and right now the start and shutdown works **much** quicker than with V14. (OSX Mojave)

 

My MacPro3,1 isn't officially supported by Mojave or Catalina so Parallels support won't look into that. I was unable to reproduce the problem on a Mac mini 2018 running Mojave or Catalina. Anyone using a supported Mac that is having a slowdown problem?

 

Yes, we have all been having this issue. It's actually forced me to start running Windows natively in bootcamp on my iMac 5K and MacBook Pro. However just today Parallels updated itself to 15.1.2 and I also upgraded to Catalina on my MacBook Pro, and it seems to work much better now! Parallels Hypervisor is a lot faster again than the Apple one, so maybe they finally fixed this?

 

Still slow with MacPro3,1, Catalina 10.15.0, 64-2 GB RAM, Parallels 15.1.2. It seems they might have changed the CPU icon in the window title bar so that it doesn't turn red when the CPU usage is 100% until you click the icon.

 

Just to add my updated experience - running on an iMac Pro (10c, 64GB) - Catalina 10.15.1 and Parallels 15.1.2 - Apple Hypervisor is still faster. Parallels Hypervisor is definitely improved since it became unusable in macOS 10.14.4 - but Apple HV still significantly faster in my tests (3D modelling, rendering with a few gaming tests too).

 

Bah, just tried it again in Parallels Hypervisor on my MacBook Pro and windows was so unusable I could not even type. Back to native Windows ....

 

What model (year) MacBook Pro?

 

MacBook Pro (15-inch, 2018) 15,1