Boot Proxmox from external USB3 SSD

[trendco]

For all who are interested:

Today i tried to Boot Proxmox-2.3 from a external USB3-SSD, but it did not work.
In search of a solution, I found: http://evilshit.wordpress.com/2012/...erver-on-a-usb-3-0-stick-and-boot-that-stick/

Summary:

add the following line to the "/etc/initramfs-tools/modules"

xhci_hcd

and create a new initrd with

update-initramfs -u

Add "rootdelay=10" to "/boot/grub.cfg" as Kernel Boot-Parameter.

...and now it works

*******************************************************

But I'm not excited about the Performance:

SSD internal

root@proxmox:/# pveperf
CPU BOGOMIPS: 18358.32
REGEX/SECOND: 992345
HD SIZE: 14.52 GB (/dev/mapper/pve-root)
BUFFERED READS: 115.68 MB/sec
AVERAGE SEEK TIME: 0.18 ms
FSYNCS/SECOND: 1611.92
DNS EXT: 105.01 ms
DNS INT: 240.97 ms (local)

SSD external (USB3) on USB-2 Port

root@proxmox:/# pveperf /mnt/pve-raid-datastore/
CPU BOGOMIPS: 18358.32
REGEX/SECOND: 1026514
HD SIZE: 147.65 GB (/dev/mapper/raid--1-pve--raid--datastore)
BUFFERED READS: 59.25 MB/sec
AVERAGE SEEK TIME: 12.10 ms
FSYNCS/SECOND: 58.22
DNS EXT: 102.32 ms
DNS INT: 218.12 ms (local)

SSD external (USB3) on USB-2 Port

root@proxmox:~# pveperf
CPU BOGOMIPS: 18358.60
REGEX/SECOND: 974935
HD SIZE: 14.52 GB (/dev/mapper/pve-root)
BUFFERED READS: 35.29 MB/sec
AVERAGE SEEK TIME: 0.32 ms
FSYNCS/SECOND: 751.95
DNS EXT: 120.03 ms
DNS INT: 282.99 ms (local)

"FSYNCS" and "AVERAGE SEEK TIME" are much better on USB3 than on USB2, but "BUFFERED READS" on USB3 are lower than on USB2 !?