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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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Specific to OSX.
Similarly for last wake time:
sysctl -a | grep waketime
Once you know the available frequencies for your CPU, they can be used to do things like set minimum CPU frequency for powerd so that it doesn't ramp down too slow on a server :
/etc/sysctl.conf or /boot/loader.conf:
debug.cpufreq.lowest=DESIRED FREQ HERE
or at terminal
sysctl debug.cpufreq.lowest=DESIRED FREQ HERE
The example is a little bit bogus, but applies to any command that takes a while interactively, or might be a bit of a drag on system resources. Once the command's output is saved to a variable, you can then echo "$OUTPUT" to see it in multi-line glory after that. The use of double-quotes around the backticks and during the variable expansion disables any IFS conversion during those two operations.
Very useful for reporting that might pull different lines out, like from dmidecode, inq or any other disk detail command. The only caveat is that storing too much in a variable might make your shell process grow.
This command allow you to set the swappiness var at 50 (default is 60). The value interval must be set between 0 and 100. If swappiness is high=Swap usage is high, if swappiness is low=Ram usage is high.
it provides the ratio used for the RAM and The SWAP under Linux. When swappiness is high, Swap usage is high. When swappiness is low, Ram usage is high.