Snapraid parity not using full cpu? Why?
by jmgibson1981 from LinuxQuestions.org on (#52WYG)
Code:PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
69320 root 20 0 246648 205232 2592 S 8.9 1.3 0:55.17 snapraidI added another parity level today. Gives me 2. Admittedly the parity drives are usb. One of my 2 data drives was a usb 3.0 drive. Replaced with an internal, and re-purposed the drive to a second parity.
I'm curious why this parity rebuild is not even coming close to my cpu ability? Floating between 8 and 11 % of a single core. Ram the same, around 1%. Is this because of I/O limits on USB 2.0 which is how I have the 2 drives plugged in? Granted I won't have to rebuild parity often but, would it be worth it to get a USB 3.0 pciX card as the drives are usb 3.0? I'm not sure but I'd bet they are on the same bus. I don't know enough about usb to ... well nothing beyond plug it in and it works, and relative speeds of each version.
69320 root 20 0 246648 205232 2592 S 8.9 1.3 0:55.17 snapraidI added another parity level today. Gives me 2. Admittedly the parity drives are usb. One of my 2 data drives was a usb 3.0 drive. Replaced with an internal, and re-purposed the drive to a second parity.
I'm curious why this parity rebuild is not even coming close to my cpu ability? Floating between 8 and 11 % of a single core. Ram the same, around 1%. Is this because of I/O limits on USB 2.0 which is how I have the 2 drives plugged in? Granted I won't have to rebuild parity often but, would it be worth it to get a USB 3.0 pciX card as the drives are usb 3.0? I'm not sure but I'd bet they are on the same bus. I don't know enough about usb to ... well nothing beyond plug it in and it works, and relative speeds of each version.