[Solved] Very slow speed for VM I/O

Discussions related to using VirtualBox on Windows hosts.
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cdg
Posts: 33
Joined: 11. Nov 2014, 04:06

[Solved] Very slow speed for VM I/O

Post by cdg »

I am using VirtualBox 5.2.32 on a Windows 10/64-bit system with a Windows XP VM to run a number of 16-bit programs that won't run under W10 (they run in a cmd.exe box on the virtual XP machine). Speeds are VERY slow when some programs are performing a lot of I/O. Something that takes a few seconds with native WXP, takes several minutes with the virtual XP machine. Similarly, MS-Word "Select all > F9 (perform calculations)" takes much longer with the virtual machine, as do several other I/O intensive 32-bit programs.

I've tried to speed it up as follows:
• Increasing "base memory" from 1024MB to 3584Mb didn’t help. More than that (with 128MB video memory) prevents the virtual machine from loading. But 1024MB works fine with a W10 (332-bit) or Linux Mint (64-bit) host.
• Enabling I/O APIC didn't help
• Can’t select multiple processors (option is greyed out on x64 host, but not on x32 or Linux host!)
• Can’t enable VT-x/AMD-V (Acceleration tab is greyed out on x64 host, but not on x32 or Linux host, which do have it selected!)
• Can’t enable Nested Paging (Acceleration tab is greyed out on x64 host, but not on x32 or Linux host, which do have it selected!)
• Increasing the display memory to 128MB didn’t help
• Enabling 3D Acceleration and/or 2D Video Acceleration didn't help
• Unchecking "Use Host I/O cache" made no difference
• Checking "Solid-state drive" made no difference, even though the .VDI file is stored on a SSD
• Excluding c:\VirtualMachines from Defender scan didn’t help, nor did disabling Avira in the VM
• Turning off indexing (in the virtual machine) didn’t help
• Defragmenting the virtual hard disk (in the virtual machine) didn't help
• Changing the power plan (in the host machine) to "high-performance" didn't help

Any other suggestions?

(Note that this does not happen with VirtualBox 5.2.32 on a Windows 10 32-bit system, or VirtualBox 5.2.32 on a Linux Mint 64-bit system with the identical Windows XP VM, but the same anomaly does occur with VirtualBox 6.0.10 on a Windows 10 64-bit system!)

SOLVED 08/11/2019: After reading viewtopic.php?f=1&t=62339, and following those suggestions, I discovered that Virtualization was not enabled in the BIOS of my new motherboard. Enabling it solved the problem. :) Many thanks to Mpack and Socrates.
socratis
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Joined: 22. Oct 2010, 11:03
Primary OS: Mac OS X other
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Guest OSses: Win(*>98), Linux*, OSX>10.5
Location: Greece

Re: [Solved] Very slow speed for VM I/O

Post by socratis »

Great, thanks for letting us know. And thank you for marking the topic as [Solved]... ;)
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