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ps aux | grep 'httpd' | awk '{print "PID ->"  $2 " MEM ->"  $6/1024 " MB";}'
watch -n 1 "echo -n 'Apache Processes: ' && ps -C httpd --no-headers | wc -l && free -m"
ps -ylC httpd --sort:rss | awk '{sum+=$8; ++n} END {print "Tot="sum"("n")";print "Avg="sum"/"n"="sum/n/1024"MB"}'

1) process tree
 pstree -p | grep httpd

2) sessions memory
ps aux | grep 'httpd' | awk '{print "PID ->"  $2 " MEM ->"  $6/1024 " MB";}'

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1) copy key to new instance. My-new-key.pem to .ssh
2) change permissions (chmod 400)
3) run as ec2-user/centos/ubuntu:
cd .ssh
ssh-keygen -f My-new-key.pem -y >> authorized_keys

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netstat -plnt

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              Wow! I Didn't Know You Could Do That In vi
 
                                          compiled by: Patricia Bender
 
ESC = the escape key
RET = the return key
char = any lowercase character
8 = any number
num = any number

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This is a quick tldr; there are many other situations and options you could consider.

FIO man page
IOP/s = Input or Output operations per second
Throughput = How many MB/s can you read/write continuously
Variables worth tuning based on your situation:

--iodepth

The iodepth is very dependant on your hardware.

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journalctl


This will display the logs with the oldest entries first.  Although this is simple, it is not very useful since we do not tend to read logs like a book.

By default journalctl displays the logs in a pager.  It shows you one page of logs requiring you to hit the space bar to proceed.  Also long log lines WILL NOT wrap, they will trail off the right side of the screen.  You can use the right arrow to see the rest of the line.

We will talk more about changing the way the logs are displayed in a different article.  Let's move on to some basic log viewing commands.

Diplaying Logs by Date

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---
- name: test if grub configured for noop i/o scheduler
  command: egrep -q 'elevator=noop' /boot/grub2/grub.cfg
  register: grub
  changed_when: no
  failed_when: grub_test.rc == 2

- name: configure grub for noop i/o scheduler
  sudo: yes
  command: grubby --update-kernel=ALL --args=elevator=noop

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#!/usr/bin/env bash
set -x -e

JUPYTER_PASSWORD=${1:-"myJupyterPassword"}
NOTEBOOK_DIR=${2:-"s3://myS3Bucket/notebooks/"}

# home backup
if [ ! -d /mnt/home_backup ]; then
  sudo mkdir /mnt/home_backup
  sudo cp -a /home/* /mnt/home_backup

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# Jupyter configuration #

c.NotebookApp.open_browser = False
c.NotebookApp.port = 9090
c.NotebookApp.password = u'sha1:somepass'
c.Authenticator.admin_users = {'hadoop'}
c.LocalAuthenticator.create_system_users = True
c.NotebookApp.contents_manager_class = 's3contents.S3ContentsManager'
c.S3ContentsManager.bucket_name = 'my-bucket'
c.S3ContentsManager.prefix = 'notebooks'

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TestService

Windows Service with Python 3.5 and pyinstaller

Requirements

• Python 3.5.x
• Visual C++ Build Tools 2015
• PyInstaller 3.2