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Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:
As of this writing, this requires a fairly recent version of util-linux, but is much simpler than the previous alternatives. Basically, lsblk gives a nice, human readable interface to all the blkid stuff. (Of course, I wouldn't recommend this if you're going to be parsing the output.) This command takes all the fun out of the previous nifty pipelines, but I felt I ought to at least mention it as an alternative since it is the most practical.
Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux.
Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU:
bc -l <(echo "1234123412341234^12341234")
See the difference `prlimit` makes:
prlimit --cpu=10 bc -l <(echo "1234123412341234^12341234")
To actually monitor the CPU usage, use `top`, `sar`, etc.. or:
pidstat -C 'bc' -hur -p ALL 1
Shows all block devices in a tree with descruptions of what they are.
`blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices.
-c /dev/null - Do not use cached output from /etc/blkid.tab or /etc/blkid/blkid.tab (RHEL)
-i - Display I/O Limits (aka I/O topology) information (not available in RHEL)
-p - Low-level superblock probing mode (not available in RHEL)