我们用库姆多年来一直致力于 Linux 主机虚拟化！这是一款很棒的工具！我们将其用于 Linux VM 和 Windows VM！
但是，我们在所有运行的虚拟机中都遇到了一个奇怪的未解决的性能问题Windows 10或者Windows 服务器 2016：处理小文件（100KB 以下）时（复制、删除）I/O 速度非常慢- 吞吐率低于 1MB/s。大文件的吞吐率最高为 35 Mb/s，仍然低于 I/O 控制器的吞吐率。
任何存储格式都会出现这个问题：raw、qcow。
Windows Server 2016 VM 上的 I/O 非常慢！文件复制操作的屏幕截图
在同一硬件上直接安装运行 Win10 或 Win Server 2016...没问题！
如果我们尝试在同一个主机上运行 Windows 7 和 Windows Server 2012 的虚拟机，我们会发现同一个文件的 I/O 速度非常快，吞吐量至少为 30MB/s！大文件的吞吐量至少为 60MB/s。
可能出了什么问题？使用原始存储设备时，我们使用来自 fedora 链接的最新 virtio 驱动程序： https://docs.fedoraproject.org/en-US/quick-docs/creating-windows-virtual-machines-using-virtio-drivers/index.html
Windows Server 2016 VM 上的 Virtio 驱动程序详细信息
4 个不同的主机上出现相同的问题！硬件设置：
主持人Centos 7 机器（CentOS Linux 版本 7.3.1611（核心））：HP ML 380 G8 服务器、192GB Ram、2 个 Xeon 处理器、SAS 存储。
虚拟机：KVM 虚拟化、Windows 10 版本 17134.590（每个 VM 至少 4GB RAM）或 Windows Server 2016 版本 1607-Build 14393.2273（每个 VM 至少 10GB RAM）
在虚拟机的 Virsh 设置下也许有人能发现一个问题！
我们认为这是驱动程序问题，但我们不知道在哪里可以找到virtio 驱动程序适用于上述 Windows 版本。
有什么想法吗？谢谢！
KVM 域描述
<domain type='kvm' id='9'>
<name>xxxx</name>
<uuid>yyyy</uuid>
<memory unit='KiB'>4194304</memory>
<currentMemory unit='KiB'>4194304</currentMemory>
<vcpu placement='static'>4</vcpu>
<resource>
<partition>/machine</partition>
</resource>
<os>
<type arch='x86_64' machine='pc-i440fx-rhel7.0.0'>hvm</type>
</os>
<features>
<acpi/>
<apic/>
<hyperv>
<relaxed state='on'/>
<vapic state='on'/>
<spinlocks state='on' retries='8191'/>
</hyperv>
</features>
<cpu mode='custom' match='exact'>
<model fallback='allow'>SandyBridge</model>
</cpu>
<clock offset='localtime'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
<timer name='hypervclock' present='yes'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<pm>
<suspend-to-mem enabled='no'/>
<suspend-to-disk enabled='no'/>
</pm>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/KVM/xxx.qcow2'/>
<backingStore/>
<target dev='vda' bus='virtio'/>
<boot order='3'/>
<alias name='virtio-disk0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<backingStore/>
<target dev='sda' bus='sata'/>
<readonly/>
<boot order='1'/>
<alias name='sata0-0-0'/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<source file='/root/Desktop/ESD_ISO.iso'/>
<backingStore/>
<target dev='sdb' bus='sata'/>
<readonly/>
<boot order='2'/>
<alias name='sata0-0-1'/>
<address type='drive' controller='0' bus='0' target='0' unit='1'/>
</disk>
<controller type='usb' index='0' model='ich9-ehci1'>
<alias name='usb'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x7'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci1'>
<alias name='usb'/>
<master startport='0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0' multifunction='on'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci2'>
<alias name='usb'/>
<master startport='2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x1'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci3'>
<alias name='usb'/>
<master startport='4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pci-root'>
<alias name='pci.0'/>
</controller>
<controller type='sata' index='0'>
<alias name='sata0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
</controller>
<controller type='virtio-serial' index='0'>
<alias name='virtio-serial0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</controller>
<interface type='network'>
<mac address='52:54:00:38:9f:70'/>
<source network='NAT' bridge='virbr0'/>
<target dev='vnet1'/>
<model type='virtio'/>
<alias name='net0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
<serial type='pty'>
<source path='/dev/pts/0'/>
<target port='0'/>
<alias name='serial0'/>
</serial>
<console type='pty' tty='/dev/pts/0'>
<source path='/dev/pts/0'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<channel type='spicevmc'>
<target type='virtio' name='com.redhat.spice.0' state='disconnected'/>
<alias name='channel0'/>
<address type='virtio-serial' controller='0' bus='0' port='1'/>
</channel>
<input type='tablet' bus='usb'>
<alias name='input0'/>
<address type='usb' bus='0' port='1'/>
</input>
<input type='mouse' bus='ps2'>
<alias name='input1'/>
</input>
<input type='keyboard' bus='ps2'>
<alias name='input2'/>
</input>
<graphics type='spice' port='5902' autoport='yes' listen='127.0.0.1'>
<listen type='address' address='127.0.0.1'/>
<image compression='off'/>
</graphics>
<sound model='ich6'>
<alias name='sound0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
</sound>
<video>
<model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
</video>
<redirdev bus='usb' type='spicevmc'>
<alias name='redir0'/>
<address type='usb' bus='0' port='2'/>
</redirdev>
<redirdev bus='usb' type='spicevmc'>
<alias name='redir1'/>
<address type='usb' bus='0' port='3'/>
</redirdev>
<memballoon model='virtio'>
<stats period='5'/>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
</memballoon>
</devices>
<seclabel type='none' model='none'/>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+107:+107</label>
<imagelabel>+107:+107</imagelabel>
</seclabel>
</domain>