Commands by kharthigeyan (2)

  • 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

    openssl speed md5
    kharthigeyan · 2019-11-07 16:30:30 6
  • Http server on port other than 8000 Show Sample Output

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

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Printable random characters
Reads psuedorandom bytes from /dev/urandom, filtering out non-printable ones. Other character classes can be used, such as [:alpha:], [:digit:] and [:alnum:]. To get a string of 10 lowercase letters: $ tr -dc '[:lower:]' < /dev/urandom | head -c 10

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Match a URL
For the record: I didn't build this. Just shared what I found that worked. Apologies to the original author! I decided I should fix the case where is not matched for the next time I need this. So I read rfc1035 and formalized the host name regex. If anyone finds any more holes, please comment.

Change mysql prompt to be more verbose
You can put this into your shell sourced file like .bashrc or .zshrc to have a different mysql prompt. See for more informations. Beware that currently with mysql 5.5 the seconds are buggy and won't be displayed if you put this into a .cnf file. With the enironment variable this will work.

Rip a video for archiving, from any site
Download video files from a bunch of sites (here is a list The options say: base filename on title, ignores errors and continue partial downloads. Also, stores some metadata into a .json file plz. Paste youtube users and playlists for extra fun. Protip: git-annex loves these files

Are the two lines anagrams?
This works by reading in two lines of input, turning each into a list of one-character matches that are sorted and compared.

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