Continuing Saga, last (I hope) episode

Continued from here. I got the disks out to the colo facility, and swapped them in. At first, things didn’t come up right because it didn’t have a network. Funny, because I’d remembered to fix /etc/network/interfaces and /etc/resolv.conf back to the values they need in the colo facility before I’d shut down at home. Grepping through the dmesg results showed that for some reason, eth0 had been renamed to eth2 and eth1 had been renamed to eth3. Something tickled my memory about the last time I’d been through this – it remembered the MAC addresses on the machine you set it up on, so when it boots the new machine it thinks “aha, I already know where eth0 and eth1 are, so these new MAC addresses need to be mapped somewhere else”. Unfortunately my own blog was down, so I couldn’t find what I’d written about this before, but a quick google on my iPhone and I removed /etc/udev/rules.d/70-persistent-net.rules, and rebooted, and it all came up.

Made sure I was talking to the net, and I could ssh into it from home, and then started up the guest domains. Made sure they were up and talking to the net as well. Made sure one of my web sites showed up on my iPhone. Buttoned up and went home.

Once I got home, I made some further checks that everything was up. As far as I can tell, it is. Now to run tiobench on the updated system.

Let’s have a look at some of these compared to the results I got with the Caviar Green disks running on the same hardware.

Test Old New
Sequential Read best rate 44.49 168.26
Random Read best rate 0.39 1.37
Read Max Latency 1036.44 743.22
Sequential Write best rate 10.36 82.46
Random Write best rate 0.09 1.76
Write Max Latency 143896.67 1748.55

Basically the huge latency will be the biggest difference. I don’t know if that’s because of the WD Caviar Green “spin down” or because there were disk errors, but either way, it’s going to be a relief to see some performance again.

Raw results after the cut.
Continue reading Continuing Saga, last (I hope) episode