Optimising disk performance inside windows VM's

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Optimising disk performance inside windows VM's

Adam Goryachev-3
I was wondering if anyone could provide hints/tips on how to "optimise"
disk performance within a Windows VM.

Specifically, I'm using Windows 2008R2 with the xen GPLPV drivers
version from

My Xen config file:

builder        = 'hvm'
memory        = 20480
name        = "server"
hostname    = "server"
localtime    = 1
cpus        = "4,5,6,7,8,9,10,11"    # Which physical CPU's to allow
vcpus        = 8        # How many Virtual CPU's to present
viridian    = 1
disk        = [ 'phy:/dev/ssd/server2,xvda,w' ]
boot        = 'dc'
vif        = ['bridge=xenbr0, mac=00:16:3e:43:ab:94']
vnc        = 1
vncunused    = 0
vncdisplay    = 5
vnclisten    = ''
stdvga        = 1
#videoram    = 16
usb        = 1
usbdevice    = 'tablet'
acpi        = 1
apic        = 1
on_reboot    = 'restart'
on_poweroff    = 'destroy'
on_crash    = 'restart'

I notice that this results in this fragment to qemu-system-i386:
I am curious if the ide part could be changed to help, or any of the
other options?

Also, this document:
talk about using a "direct-io-safe" option, which can improve
performance, where would I add that?
disk        = [ 'phy:/dev/ssd/server2,xvda,w,direct-io-safe=present' ]

Essentially, I have a simple linux software RAID1 on two SSD's, which is
setup as a PV, I have a single LV which is then used as the disk image.
I've seen lots of various options that can be used for the disk
type/options/etc, but I don't really know which is the "best".

I'm using Xen 4.8.3 from Debian stable packages:
ii  grub-xen-bin 2.02~beta3-5                            amd64       
GRand Unified Bootloader, version 2 (Xen binaries)
ii  grub-xen-host 2.02~beta3-5                            amd64       
GRand Unified Bootloader, version 2 (Xen host version)
ii  libxen-4.8:amd64 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5
amd64        Public libs for Xen
ii  libxenstore3.0:amd64 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5
amd64        Xenstore communications library for Xen
ii  xen-hypervisor-4.8-amd64 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5
amd64        Xen Hypervisor on AMD64
ii  xen-linux-system-amd64 4.9+80+deb9u4                          
amd64        Xen system with Linux for 64-bit PCs (dummy package)
ii  xen-system-amd64 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5
amd64        Xen System on AMD64 (meta-package)
ii  xen-utils-4.8 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5 amd64       
XEN administrative tools
ii  xen-utils-common 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5
all          Xen administrative tools - common files
ii  xenstore-utils 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5 amd64       
Xenstore command line utilities for Xen

Kernel version is 4.9.82-1+deb9u3

If I should add any additional information, please let me know.


Adam Goryachev Website Managers www.websitemanagers.com.au
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