Commands tagged performance sorted by votes

Commands tagged performance (8)

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Manually Pause/Unpause Firefox Process with POSIX-Signals

Continue with: killall -CONT -m firefox Suspends all Firefox Threads. Results in Zero CPU load. Useful when having 100+ Tabs open and you temporarily need the power elsewhere. Be careful - might produce RACE CONDITIONS or LOCKUPS in other processes or FF itself. matching is case sensitive.
This is sample output - yours may be different.
26

killall -STOP -m firefox

Schneckentreiber · 2009-05-18 20:02:44 16
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
This is sample output - yours may be different.
```
Doing md5 for 3s on 16 size blocks: 11406892 md5's in 2.98s
Doing md5 for 3s on 64 size blocks: 8479926 md5's in 2.99s
Doing md5 for 3s on 256 size blocks: 4800618 md5's in 2.99s
Doing md5 for 3s on 1024 size blocks: 1719000 md5's in 2.98s
Doing md5 for 3s on 8192 size blocks: 249448 md5's in 2.99s
```
10

openssl speed md5

kharthigeyan · 2019-11-07 16:30:30 221
Download file with multiple simultaneous connections

`aria2c` (from the aria2 project) allows. Change -s 4 to an arbitrary number of segments to control the number of concurrent connections. It is also possible to provide multiple URLs to the same content (potentially over multiple protocols) to download the file concurrently from multiple hosts.
This is sample output - yours may be different.
8

aria2c -s 4 http://my/url

jrk · 2009-08-11 22:34:00 11
Download file with multiple simultaneous connections

jrk's aria2 example is incorrect. -s specifies the global connection limit; the per-host connection limit is specified with -x.
This is sample output - yours may be different.
6

aria2c -x 4 http://my/url

lx45803 · 2014-07-26 03:06:33 12
Performance tip: compress /usr/

Periodically run the one-liner above if/when there are significant changes to the files in /usr/ = Before rebooting, add following to /etc/fstab : = /squashed/usr/usr.sfs /squashed/usr/ro squashfs loop,ro 0 0 usr /usr aufs udba=reval,br:/squashed/usr/rw:/squashed/usr/ro 0 0 No need to delete original /usr/ ! (unless you don't care about recovery). Also AuFS does not work with XFS
This is sample output - yours may be different.
4

[ ! -d /squashed/usr ] && mkdir -p /squashed/usr/{ro,rw} ; mksquashfs /usr /squashed/usr/usr.sfs.new -b 65536 ; mv /squashed/usr/usr.sfs.new /squashed/usr/usr.sfs ; reboot

mhs · 2014-05-10 06:01:06 10

fork performance test

grabbed from Andrew Aylett post: http://superuser.com/questions/133313/can-i-speed-up-cygwins-fork Show Sample Output

while (true); do date --utc; done | uniq -c

hute37 · 2013-03-15 12:05:37 40

Find processes blocked on IO
This is sample output - yours may be different.
0

while [ 1 ] ;do ps aux|awk '{if ($8 ~ "D") print }'; sleep 1 ;done

paulp · 2014-01-21 08:20:04 7
Percental CPU scaled load average

This “sysload” alias converts the load average to percentages and divides them by the number of CPUs/cores. It may provide a more intuitive guesstimate of how much work the server is doing. Show Sample Output
This is sample output - yours may be different.
```
$ sysload

System load (1m/5m/15m): 31,5% 30,0% 29,8%
```
0

alias sysload='printf "System load (1m/5m/15m): "; for l in 1 2 3 ; do printf "%.1f%s" "$(( $(cat /proc/loadavg | cut -f $l -d " ") * 100 / $(nproc) ))" "% "; done; printf "\n"'

lordtoran · 2021-03-27 17:10:53 239

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pretend to be busy in office to enjoy a cup of coffee

Dialog's gauge widget accepts progress updates on stdin. This version runs dialog once and updates it every second. There's no need to use timeout which causes screen flicker since it restarts dialog for each update.

list files recursively by size

Currency Conversion

eg: currency_convert 1 usd inr

Generate QR code for a WiFi hotspot

Prompts for network name (SSID) and password, and generates (as qr-wifi.png) a WiFi QR code (e.g. "WIFI:S:mynet;T:WPA;P:mypass;;" for mynet/mypass). Dependencies [sudo apt-get install]: qrencode zenity

Install pip with Proxy

Installs pip packages defining a proxy

Rename duplicates from MusicBrainz Picard

Renames duplicates from MusicBrainz Picard, so you get the latest copy and not a bunch of duplicates.

Read just the IP address of a device

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"

Rename files in batch

See how many more processes are allowed, awesome!

There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100. $ OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 $ -user $USER -o -group $GROUPNAME $ -type d|wc -l`) / 2 )) This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript). An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command. $ find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this: $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this. $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' If you were building a process-killer (very common for cheap hosting) this would also be handy. Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

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Commands tagged performance (8)

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