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Thread: usb drive performance in kvm

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hi,

host: karmic
guest: linux sysrescuecd 2.6.29.06-sd123 #1 smp ...

have connected external usb drive , performance in guest way below expectations. hdparm -t reports 2mb in 5 sec.
same drive connected host reports: 90 mb in 3.05 seconds = 29.49 mb/sec

start kvm with:
sudo kvm -enable-kvm -boot d -vga vmware -hda disk0 -cdrom ~/download/iso/systemrescuecd-x86-1.2.3.iso -usb -usbdevice host:1058:0704


have on host? until unmounted whatever got mounted in /media before starting kvm

--pawel

i have exact same problem. i'm running 9.10 64-bit server on dell tower, core2 duo e8400 @ 3 ghz, 4 gigs ram.

external drive western digital book 1110, single 500gig drive. drive has "feature" of built-in fake cd drive bunch of western digital drivers/manuals/etc.

code:
user@server:~$ sudo hdparm -t /dev/sdb1    /dev/sdb1:   timing buffered disk reads:    2 mb in  4.94 seconds = 414.92 kb/sec
as far can tell, external drive connected guest vm @ usb 2.0 speeds, measured speed usb 1.1. not i'm looking for.

maybe has apparmor?


Forum The Ubuntu Forum Community Ubuntu Specialised Support Virtualisation [ubuntu] usb drive performance in kvm


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