Commands by kharthigeyan (2)

  • Host cpu performance

    Measure the cpu performance: In-case if the cpu is thermal throttling then you can find it using this command. Check the first line of the output. Example: Doing md5 for 3s on 16 size blocks: 11406892 md5's in 2.98s ? #(When cpu is not throttling) Doing md5 for 3s on 16 size blocks: 110692 md5's in 2.98s ?? #(When cpu is thermal throttling) Practical use case: Once we had cooling outage in data center which caused thermal throttling in some of the worker nodes. We used this tool to prove that some servers are not performing well because of the cpu thermal throttling. Show Sample Output


    10
    openssl speed md5
    kharthigeyan · 2019-11-07 16:30:30 121
  • Serve current directory tree at http://$HOSTNAME:8000/

    Http server on port other than 8000 Show Sample Output


    0
    python -m SimpleHTTPServer 8080
    kharthigeyan · 2019-02-12 14:53:57 29

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convert ascii string to hex
Even adds a newline.

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Perform sed substitution on all but the last line of input
In this simple example the command will add a comma to the end of every line except the last. I found this really useful when programatically constructing sql scripts. See sample output for example.

Run the Firefox Profile Manager
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Recover resolution when a fullscreen program crashes and you're stuck with a tiny X resolution
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backup local MySQL database into a folder and removes older then 5 days backups

Burn CD/DVD from an iso, eject disc when finished.
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Delete all empty/blank lines from text file & output to file

Loop over the days of a month, in $YYYY$MM$DD format
Edit YYYY and MM at the beginning of the command with the year and month you want. Note that `DD=$(printf "%02d" $d)` will pad single digit integers with a leading zero. Substitute `echo $YYYY$MM$DD` at the end of the line with the command you want to launch, for instance script.pl --yyyymmdd $YYYY$MM$DD Also available on GitHub as bash util: https://github.com/fibo/yyyymmdd

network interface and routing summary

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