How to automate the Offline compaction process in AEM 6.2

Statement  : Automate the offline compaction process.

Solution :

• For Offline compaction is still applicable for AEM 6.2 but AEM 6.3 is not required beacuse it spports online compaction.
• Below is the steps involved in the automation and script which is used automates entire process.

Steps involved in the Offline compaction Automation :

1. Shutdown AEM Server
2. Use Matching Oak jar version to find Old Checkpoints
3. Use Matching Oak jar version to Remove Unreferenced Checkpoints
4. Use Matching Oak jar version to Compact Oak
5. Restart AEM

SCRIPT:

#!/bin/bash

todayDate="$(date +'%d-%m-%Y')"

logfile="compact-$ todayDate.log"

installfolder="/data/aem"

aemfolder="$installfolder/crx-quickstart"

oakrun="$installfolder/help/oak-run-1.6.1.jar"

## Shutdown AEM

printf "Shutting down AEM.\n"

$aemfolder/bin/stop

todayDate ="$(date)"

echo "AEM Shutdown at: $ todayDate " >> $installfolder/help/logs/$logfile

## Find old checkpoints

printf "Finding old checkpoints.\n"

java -Dtar.memoryMapped=true -Xms8g -Xmx8g -jar $oakrun checkpoints $aemfolder/repository/segmentstore >> $installfolder/help/logs/$logfile

## Delete unreferenced checkpoints

printf "Deleting unreferenced checkpoints.\n"

java -Dtar.memoryMapped=true -Xms8g -Xmx8g -jar $oakrun checkpoints $aemfolder/repository/segmentstore rm-unreferenced >> $installfolder/help/logs/$logfile

## Run compaction

printf "Running compaction. This may take a while.\n"

java -Dtar.memoryMapped=true -Xms8g -Xmx8g -jar $oakrun compact $aemfolder/repository/segmentstore >> $installfolder/help/logs/$logfile

## Report Completed

printf "Compaction complete. Please check the log at:\n"

printf "$installfolder/help/logs/$logfile\n"

## Start AEM back up

todayDate ="$(date)"

printf "Starting up AEM.\n"

$aemfolder/bin/start

echo "AEM Startup at: $ todayDate " >> $installfolder/help/logs/$logfile

Reference :

https://jackrabbit.apache.org/oak/docs/command_line.html

How to find Popular and Slow Queries in AEM through JMX console

Statement - Popular and Slow Queries in AEM through JMX console
Environment - AEM 6.3 GA

Solution :

• Go to the Felix console URL: http://localhost:4502/system/console/jmx/org.apache.jackrabbit.oak%3Aname%3DOak+Query+Statistics%2Ctype%3DQueryStat
• You can observe the top 15 popular queries as shown in below screenshot. 

• Top 15 Slow Queries tweak slow queries/rewrite slow queries for better performance or create indexes for those slow queries.

• Below is the screenshot to clear popular and slow queries, Click on each of the below Operation and click on invoke.

• That's  it!

Oak QueryEngine Optimization Parameters and how to set these parameter in JMX console in AEM

Statement - Query engine Optimization parameters
Environment - AEM 6.3 GA

Solution :

• Go to the Felix console URL: http://localhost:4502/system/console/jmx/org.apache.jackrabbit.oak%3Aname%3Dsettings%2Ctype%3DQueryEngineSettings
• below are the QueryEngine parameters and set the values based on need.

Attributes
Attribute Name	Attribute Value
LimitInMemory	500000
LimitReads	100000
FailTraversal	true
FastQuerySize	false

• Click on  each of these attribute value to increase/decrease as shown in below.

• To return the query result size should return an estimation for large queries set the FastQuerysize to True
  
• Set FailTraversal to True Whether queries that don't use an index will fail (throw an exception) as shown in below screenshot.
  

• That's  it!