Hot deploy in jboss

https://community.jboss.org/wiki/JBoss51DisableEnableHotDeployHDScanner

DB Oracle Important Stats to monitor

1) Buffer Cache hit ratio. This should be high as the  data is needs to be read from cache. Also the disk i/o is less if it is read from cache.
2) Cache hit ratio
3) Library cache.. where sql,pl/sql, re-usable sql are placed
4)soft parsing should be high compared to hard parsing... as the time spent in parsing sqls is less softparsing. (Softparsing->hardParsing->Explain plan)

jmx-console

http://www.blogsoncloud.com/jsp/blogs/using-jboss-jmx-console.jsp

Analyzing AWR Report

http://www.pafumi.net/AWR%20Reports.html

Using JMX-Console to get Thread Dumps

https://community.jboss.org/wiki/GenerateAThreadDumpWithTheJMXConsole

JBOSS and OS tuning

http://middlewaremagic.com/jboss/?cat=4

Apache MPM Prefork vs Worker

https://communities.ca.com/web/ca-identity-and-access-mgmt-distributed-global-user-community/message-board/-/message_boards/view_message/98290538

This Tuesday Tip will cover some common questions regarding Apache, specifically prefork vs. worker mode, how to change the default value on RedHat, Solaris and other operating systems as well as verifying what mode apache is currently running in.

A. The default MPM for Unix is the Prefork module. 
B. The Worker MPM was introduced in Apache2. 

Now Comparing between Worker MPM and Prefork MPM.

Prefork MPM 
- prefork MPM uses multiple child processes with one thread each. 
- Each process handles one connection at a time and uses more memory. 
- Good for non-thread-safe third party modules. 

Worker MPM 
- worker MPM uses multiple child processes with many threads each. 
- Each thread handles one connection at a time. 
- Good for high-traffic, smaller memory footprint. 

MPM uses a multi-process and multi-threaded structure. 
Multi-process --> multi PIDs (use 'ps -aef' to find out) 
Multi-thread --> more connections per PID. (use 'lsof' (on Solaris) to find out. 'netstat -an' (You really won’t see everything.) 

The worker MPM uses multiple child processes. It's multi-threaded within each child, and each thread handles a single connection. Worker is fast and highly scalable and the memory footprint is comparatively low. It's well suited for multiple processors.

Prefork MPM is preferred for better compatibility with older software or for better stability although it uses more memory. It handles requests in a manner similar to Apache 1.3. It is appropriate for sites that need to avoid threading for compatibility with non-thread-safe libraries. It is also the best MPM for isolating each request, so that a problem with a single request will not affect any other. Prefork is well suited for single or double CPU systems, speed is comparable to that of worker, and it's highly tolerant of faulty modules and crashing children - but the memory usage is high, and more traffic leads to greater memory usage.

Conclusion: For most new websites that are that use thread safe libraries, use multiple processes and high traffic sites, CA SiteMinder recommends MPM worker mode for Apache.

>>>>>>>>>>>

How to tell if I’m running Apache in prefork or worker MPM? (Multi-Processing Module)

Note : You can have one and only one MPM module loaded in apache at any one time. 

From the bin directory, you can run ./apachectl -V (Capital V)

./apache2/bin/apachectl -V
Server version: Apache/2.0.50
Server built: Aug 3 2004 16:52:20
Server's Module Magic Number: 20020903:8
Architecture: 32-bit
Server compiled with....
-D APACHE_MPM_DIR="server/mpm/prefork" (This is running in prefork mode)

Newer version running in worker mode:

./apachectl -V
Server version: Apache/2.2.21 (Unix)
Server built: Oct 23 2011 17:42:11
Server's Module Magic Number: 20051115:30
Server loaded: APR 1.4.5, APR-Util 1.3.12
Compiled using: APR 1.4.5, APR-Util 1.3.12
Architecture: 32-bit
Server MPM: Worker <------Worker
threaded: yes (fixed thread count)
forked: yes (variable process count)
Server compiled with....
-D APACHE_MPM_DIR="server/mpm/worker" <- This same line will still exist.


A second way to check, again from the bin directory:

#./ httpd -l 
Compiled in modules: 
core.c 
prefork.c <---- Prefork
http_core.c 
mod_so.c

./httpd -l
Compiled in modules:
core.c
mod_access.c
mod_auth.c
mod_include.c
mod_log_config.c
mod_logio.c
mod_env.c
mod_setenvif.c
worker.c <-----Worker

>>>>>>>>>>>

How do I change the default value on RHEL (Red Hat Enterprise Release)?

Edit the /etc/sysconfig/httpd file.

Change #HTTPD=/usr/sbin/httpd.worker

to

HTTPD=/usr/sbin/httpd.worker

and stop/start the apache service.

>>>>>>>>>>>

Solaris or most unix like operating systems.

When I download the code from apache.org and use certain flags to compile apache, what flag do I use for worker mode?

./configure --with-mpm=worker

For all compile options, please reference www.apache.org

Apache Bench results for prefork:
Requests per second: 20.91 [#/sec] (mean)

Apache Bench results for prefork:
Requests per second: 40.94 [#/sec] (mean)





How to install Worker MPM:
http://kmaiti.blogspot.in/2012/02/how-to-start-apache-uisng-worker-mpm.html

http://articles.slicehost.com/2010/5/19/configuring-the-apache-mpm-on-centos


http://www.virtualmin.com/node/15046
http://articles.slicehost.com/2010/5/19/apache-configuration-files-on-centos
http://articles.slicehost.com/2010/5/19/configuring-the-apache-mpm-on-centos

Apache Prefork VS Worker MPM

https://communities.ca.com/web/ca-identity-and-access-mgmt-distributed-global-user-community/message-board/-/message_boards/view_message/98290538

Write simple Rest API with Java and Spring

http://eugenedvorkin.com/how-to-code-rest-api-with-java-and-spring-3-0/

Rest Tutorial

http://rest.elkstein.org/2008/02/more-complex-rest-requests.html

JBOSS Thread Pools Description

http://zeroproductionincidents.wordpress.com/tag/ajp-thread-pool/

Performance Article Google

https://developers.google.com/speed/articles/

Vim editor for timestamp

vim editor regex to update timestamp in jmeter results file
:%s/2012-\d\d-25/2012-02-25/g

sqlplus output to file with out display and trims on

http://blog.niklasottosson.com/?p=761

http://stackoverflow.com/questions/6813210/oracle-sqlplus-saving-output-in-a-file-but-dont-show-on-screen

SET echo off

02	SET feedback off

03	SET linesize 100

04	SET pagesize 0

05	SET sqlprompt ''

06	SET trimspool on

07	SPOOL filename.csv

08

set Termout off

09	SELECT field1 || ',' || field2 || ',' || field3 FROM tablename;

10

11

SPOOL off

12

exit st

Linux imp commands

http://www.fromdev.com/2008/12/debugging-java-on-unixlinux-my-favorite.html

TCP Network analysis

http://www.cyberciti.biz/tips/linux-investigate-sockets-network-connections.html

Determine Threads with High CPU usage

http://blogs.manageengine.com/appmanager/2011/02/09/identify-java-code-consuming-high-cpu-in-linux-linking-jvm-thread-and-linux-pid/

Convert Decimal to hexaecimal:
http://www.mathsisfun.com/binary-decimal-hexadecimal-converter.html

Webserver precompress static files

http://mark.aufflick.com/blog/2007/12/06/serve-pre-compressed-content-with-apache

JBOSS ACCESS LOGS

http://docs.jboss.org/jbossweb/2.1.x/config/valve.html

Linux Admin Essentials performance and more

http://www.cyberciti.biz/tips/top-linux-monitoring-tools.html

Thread Analysis

grep "\- waiting on" filename | awk '{print $4;}'|sort | uniq -c

cat API_100_0417_1|grep java.lang.Thread.State| awk '{print $2;}'|sort | uniq -c

Generate AWR Report

1. su – oracle
2. sqlplus “/ as sysdba”
3. SQL> @$ORACLE_HOME/rdbms/admin/awrrpt.sql

responsetime from webserverlogs

cat access_log.2012-03-29|awk '{print $7, $20}'| sed 's/\/[^a-z]/ /g'

Nmon Tool and usage

http://www.ibm.com/developerworks/aix/library/au-analyze_aix/

sqlplus install error resolution

http://www.yoursearchbuddy.com/sqlplus-error-loading-shared-libraries-libsqlplusso

the above solution is for the following error:
./sqlplus: error while loading shared libraries: libsqlplus.so

regex jmeter

'....oken=([^']*)';

id=(.*); Path

awk print coulmns from last of a line

awk ' { print ( $(NF) ) }' --> Last column
awk ' { print ( $(NF-3) ) }'  --> 3rd from Last column

awk command to get max value from a file

cat filename |awk 'max=="" || $1 > max {max=$1} END{ print max}'

wWebserver Analysis tools

http://code.google.com/p/wtop/

concurrency from webserver access logs

cat access_log.******* |awk '{print $1,$4,$5,$6,$7}'|awk '{print $2}'|sort | uniq -c

finding larger files in linux

http://www.cyberciti.biz/faq/find-large-files-linux/

Jmeter Javascript rendering fix

http://blazemeter.com/blog/new-jmeter-releases-whole-new-fairy-tale

TCP_DUMP

http://www.alexonlinux.com/tcpdump-for-dummies


tcpdump -ni eth1 -w file.cap -s 0 -c 1000 not port 22

Thread Contentions

http://www.ibm.com/developerworks/java/library/j-threads2/index.html

http://www.concentric.net/~ttwang/tech/syncbottle.htm

http://dev.blogs.nuxeo.com/2011/07/detecting-threads-contention.html


Well Eplained in Detail:
https://community.dynatrace.com/community/display/PUB/Identify+Thread+Contention+-+Guest+Article+by+Lucy+Monahan

Free Memory in Linux

Actual Free Memory in Linux = Free+ Buffer+Cache

Linux uses RAM to load the Disk data in RAM (emory) as reading data from memory is faster. As the needs for memory to other process increases it shrinks the cahced data accordingly.

http://blog.scoutapp.com/articles/2010/10/06/determining-free-memory-on-linux

Oracle Analytical functions

http://www.orafaq.com/node/55

calculate avg and 90th percentile from awk command

Average:

cat <filename> |grep HOME|grep "Number of samples"|awk -F "," '{sum+=$2} END { print "Average = ",sum/NR}'

95^th Percentile:

cat <filename> |grep HOME|grep "Number of samples"|awk -F "," '{print $2}' |sort -n|awk 'BEGIN{i=0} {s[i]=$1; i++;} END{print s[int(NR*0.95-0.5)]}'

calculate avg of a column

awk '{ s += $1 } END { print "sum: ", s, " average: ", s/NR, " samples: ", NR }' rails_production_log_or_whatever.log

AWk command to cut a big file into small files at a repeatative word

awk '/selected./{n++}{print >"out" n ".txt" }' partitionbased_cc_acc_ids.txt

here "selected." is the repeatative word..

Data_partitioning for scale

http://java-persistence-performance.blogspot.in/2011/05/data-partitioning-scaling-database.html

http://databasewisdom.com/partit_ora1.shtml


Awesome:
http://www.shutdownabort.com/dbaqueries/Structure_Partitions.php

Oracle sql tuning

http://www.credmond.net/oracle/tuning/
http://www.myoracleguide.com/s/OracleTips.htm

How to get the list of sqls that are CPU intensive and Waiting
http://uhesse.wordpress.com/2010/07/08/performance-monitoring-active-session-history-at-work/

remove lines in a file in Linux

sed '1,10d' server.log
command to remove lines between the line numbers 1 and 10..

http://en.kioskea.net/faq/1451-sed-delete-one-or-more-lines-from-a-file

Extract rows from a file unique w.r.t column

awk '!_[$1]++' filename

Here rows are extracted w.r.t unique values from column 1.

load average description of top command in linux

http://en.wikipedia.org/wiki/Load_(computing)

Quartz cron job scheduling in properties

http://sanjaal.com/java/tag/cron-expression-quartz-schedulers/

Jmeter JDBC Configuration for oracle,sqlserver,mysql,postgresql,apachederby,ingres

http://jmeter.apache.org/usermanual/component_reference.html#JDBC_Connection_Configuration

GEt Dbname in oracle

SQL> SELECT VALUE FROM V$PARAMETER WHERE NAME='db_name';

VALUE
--------------------------------------------------------------------------------
XXXXXXX

Oracle Connect as sysdba error..

SQL> conn / as sysdba
ERROR:
ORA-12162: TNS:net service name is incorrectly specified


SQL> exit

[qysprffinwkdb01:/home/oracle](Perf)% export ORACLE_SID=xxxxxx

[qysprffinwkdb01:/home/oracle](Perf)% echo $ORACLE_SID

xxxxxx

[qysprffinwkdb01:/home/oracle](Perf)% sqlplus "/ as sysdba"

SQL*Plus: Release 10.2.0.5.0 - Production on .........

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

Connected to:

Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production

With the Partitioning, Real Application Clusters, OLAP, Data Mining

and Real Application Testing options

SQL>

Jmeter starting from Command line

http://jmeter.apache.org/usermanual/get-started.html

AWk command for .csv files

http://stackoverflow.com/questions/7857090/awk-extract-specific-columns-from-delimited-file