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Does your physical host have 4 cores per processor? If not, can you change your guest OS to 2 processor * 2 cores/per processor and try again? Thanks!
Thanks for the reply.
The host processor is 4 core / 8 thread with all power saving features disabled (e.g. Speed Step).
Even though it is 4 core, I thought I'd re-run the NVMe preallocated case above with only 2 cores assigned. The results are almost identical
What should I try next?
Any further suggestions?
I’m also having the same problems.
Host: Threadripper 1950X, 32GB, Corsair MP510 NVMe
Guest: Windows 10, 16GB.
This is an issue for me too
Win10 host 32 GB ram i7 8 processors
Win10 guest 16GB ram, installed on SSD Samsung 970 EVO, different disk from installation of vmware workstation.
Atto benchmark results on disk where VM is hosted, run from host:
I/O size write read
512 B 27.15 mb/s 36.62 mb/s
1 MB 1.42 GB/s 3.1 GB/s
Atto benchmark results, running inside guest, accessing the same SSD:
I/O size write read
512 B 5 mb/s 6.39 mb/s
1 MB 1.1 GB/s 1.13 GB/s
almost 5 times slower in guest at 512B
half as fast at 512 MB io size.
I tried NMVe driver and it didn't make a difference
Version 15.5 VM workstation pro.
I created a brand new VM and installed windows 10 from scratch.. no difference
followed these recommendations from knowledge base:
I am stumped.
Kind of old thread. This is oranges to apples, but I doubt if your problem is all due to VM. I would suspect anti-virus, anti-intrusion or some other anti-get-stuff-done software on host.
I run a Linux host. The host is on a small SSD. I run Linux VM's on another SSD and Windows VM's on a third SSD.
Read test on the Linux VM SSD itself:
lou@T5810:~$ sudo hdparm -t /dev/sdb
Timing buffered disk reads: 1550 MB in 3.00 seconds = 516.35 MB/sec
Read test on same SSD but from a Linux Mint VM (sda in the VM)
lou@mint191:~$ sudo hdparm -t /dev/sda
Timing buffered disk reads: 1460 MB in 3.01 seconds = 485.26 MB/sec
Less than 10% difference.
I can't compare the same for the W10 VM, but with 2 W10 VM's running, I get the below result. I would guess that it would be better on a hardware W10.
VM has 1 Proc, 2 cores and 4GB. There is (normal) a bunch of disk activity at almost all times. I would look at your hosts disk activity when running your tests. I would turn off/uninstall AV, Defender, etc and try again.
w10vmspeed.PNG 32.6 K