A few weeks ago I started comparing the power consumption of low power x86(Atom) and ARM systems under load. For this I was interested in accurately measuring the power consumption at a high sample rate. At first I started with Ladyada's "Tweet-A-Watt" project which piggy backs the main op-amp of a P4400 Kill-A-Watt(KAW) by connecting it's sense-lines to the Analog-to-Digital Converter(ADC) inputs of an XBee transmitter.
Nigel's monitor(link), dubbed "Nmon", is a fantastic tool for monitoring, recording and analyzing a Linux/*nix system's performance over time. Nmon was originally developed by IBM and Open Sourced in the summer of 2009. By now Nmon is available on just about every linux platfrom and architechture. It provides a great real-time command line visualization of current system statistics, such as CPU, RAM, Network and Disk I/O. However, Nmon's greatest feature is the capability to record system performance snapshots over time. For example: "nmon -f -s 1".
I had a 500GB harddrive and with 4 primary partitions and I had run out of space. Time to upgrade of a 750GB harddrive. I had done this plenty times before, from a 160GB to a 320GB to a 500GB drive just in this laptop. But after the last upgrade I added a 100GB LUKS encrypted LVM for some work related files. This had pushed my partition count to 3 primary and 1 extended with the LUKS LVM at the end of the disk.
I have been meaning to setup my backup server with an encrypted partition on a mirrored RAID1 device. Ill be giving you guys a quick walk through on how to set this up under Debian/Ubuntu. (Other distros will be similar)
First you need 2 same size disks, I have 2x 2TB Seagate ST2000DL003