Apache Tomcat Performance optimization

Posted on June 20, 2015June 20, 2015 by coder

1- Memory problems

# Find the catalina.sh   file, 
export CATALINA_OPTS="-Xms256m -Xmx256m"
#change 256 to 128  or what every you want

# Find the catalina.sh file,

export CATALINA_OPTS="-Xms256m -Xmx256m"

#change 256 to 128 or what every you want

The Heap: This is the memory used to store your objects and is controlled by the -Xms and -Xmx parameters.

The Stack: This is the memory used to store the stack frames for the threads that your program maintains and can be controlled with the -Xss parameter.

Permgen Memory: This is the memory used to store your compiled classes and pooled strings as well as some other things and can usually be controlled with -XX:MaxPermSize although the -XX represents a debugging parameter, so there's no guarantee it's on all JVM's. But, the default Sun/Oracle reference implementations have always had them.

JNI Allocated Memory Any classes utilizing native methods and JNI could potentially allocate unlimited memory. This memory comes from the OS and not the heap and there's no way of knowing how much memory a native class will use without having access to the source.

The Heap: This is the memory used to store your objects and is controlled by the -Xms and -Xmx parameters.

The Stack: This is the memory used to store the stack frames for the threads that your program maintains and can be controlled with the -Xss parameter.

Permgen Memory: This is the memory used to store your compiled classes and pooled strings as well as some other things and can usually be controlled with -XX:MaxPermSize although the -XX represents a debugging parameter, so there's no guarantee it's on all JVM's. But, the default Sun/Oracle reference implementations have always had them.

JNI Allocated Memory Any classes utilizing native methods and JNI could potentially allocate unlimited memory. This memory comes from the OS and not the heap and there's no way of knowing how much memory a native class will use without having access to the source.

2- CPU ( For number of Threads, server.xml)

1- Limit the number of Java threads.

2- Limit the maximum Java heap size.

1- Limit the number of Java threads.

2- Limit the maximum Java heap size.

Example

<Connector port="8080" address="localhost"     
     minSpareThreads="20" />

1 2	<Connector port="8080" address="localhost" minSpareThreads="20" />

get user courses via php, $ DB-> list _ categories

Posted on June 17, 2015July 19, 2015 by coder

<?php
$mycourses = get_my_courses($USER->id);
$catArr = array();

foreach ($mycourses as $mycourse){
array_push($catArr,$mycourse->category);
}

$catArr = array_unique($catArr);

sort($catArr);

foreach ($catArr as $cat){
$myCat = get_records_select('course_categories',"id='$cat'",'name ASC','id, name');
foreach ($myCat as $mCat){
echo '<h4>'.$mCat->name.'</h4>';
}
echo '<ul>';
foreach ($mycourses as $mycourse){
if ($mycourse->category == $cat){
echo '<li><a href="../course/view.php?id='.$mycourse->id.'">'.$mycourse->fullname.'</a></li>';
}
}
echo '</ul>';
}
?>

<?php

$mycourses = get_my_courses($USER->id);

$catArr = array();

foreach ($mycourses as $mycourse){

array_push($catArr,$mycourse->category);

}

$catArr = array_unique($catArr);

sort($catArr);

foreach ($catArr as $cat){

$myCat = get_records_select('course_categories',"id='$cat'",'name ASC','id, name');

foreach ($myCat as $mCat){

echo '<h4>'.$mCat->name.'</h4>';

}

echo '<ul>';

foreach ($mycourses as $mycourse){

if ($mycourse->category == $cat){

echo '<li><a href="../course/view.php?id='.$mycourse->id.'">'.$mycourse->fullname.'</a></li>';

}

echo '</ul>';

}

Custom errors in ASP.net MVC

Posted on June 14, 2015 by coder

To enable custom errors in ASP.NET MVC application we need (IIS 7+):

Configure custom pages in web config under system.web section:

<customErrors mode="RemoteOnly"  defaultRedirect="~/error">
    <error statusCode="404" redirect="~/error/kutayzorlu404" />
    <error statusCode="500" redirect="~/error" />
</customErrors>


	HttpContext.Current.Response.StatusCode = 500;
  	HttpContext.Current.Response.TrySkipIisCustomErrors = true;


<httpErrors errorMode="Detailed" />

To enable custom errors in ASP.NET MVC application we need (IIS 7+):

Configure custom pages in web config under system.web section:

</customErrors>

HttpContext.Current.Response.StatusCode = 500;

HttpContext.Current.Response.TrySkipIisCustomErrors = true;

Linux Kernel Module Programming Guide

Posted on June 12, 2015June 12, 2015 by coder

Using /proc For Input,

Talking To Device Files,

System Calls,

Blocking Processes,

Replacing Printks,

Character Device Files,

Preliminaries,

Scheduling Tasks,

Symmetric Multi Processing,

Common Pitfalls

Please Download file from here : CLICK >> lkmpg_kutayzorlu

Foreword…………………………………………………………………………………………………………………………………………..1 1. Authorship………………………………………………………………………………………………………………………….1 2. Versioning and Notes……………………………………………………………………………………………………………1 3. Acknowledgements………………………………………………………………………………………………………………1 Chapter 1. Introduction……………………………………………………………………………………………………………………..2 1.1. What Is A Kernel Module?…………………………………………………………………………………………………2 1.2. How Do Modules Get Into The Kernel?……………………………………………………………………………….2 1.2.1. Before We Begin………………………………………………………………………………………………………3 Chapter 2. Hello World……………………………………………………………………………………………………………………..5 2.1. Hello, World (part 1): The Simplest Module…………………………………………………………………………5 2.1.1. Introducing printk()…………………………………………………………………………………………………..6 2.2. Compiling Kernel Modules………………………………………………………………………………………………..6 2.3. Hello World (part 2)…………………………………………………………………………………………………………..7 2.4. Hello World (part 3): The __init and __exit Macros………………………………………………………………8 2.5. Hello World (part 4): Licensing and Module Documentation………………………………………………….9 2.6. Passing Command Line Arguments to a Module…………………………………………………………………11 2.7. Modules Spanning Multiple Files………………………………………………………………………………………13 2.8. Building modules for a precompiled kernel…………………………………………………………………………15 Chapter 3. Preliminaries………………………………………………………………………………………………………………….17 3.1. Modules vs Programs……………………………………………………………………………………………………….17 3.1.1. How modules begin and end…………………………………………………………………………………….17 3.1.2. Functions available to modules…………………………………………………………………………………17 3.1.3. User Space vs Kernel Space……………………………………………………………………………………..18 3.1.4. Name Space……………………………………………………………………………………………………………18 3.1.5. Code space……………………………………………………………………………………………………………..19 3.1.6. Device Drivers………………………………………………………………………………………………………..19 Chapter 4. Character Device Files……………………………………………………………………………………………………21 4.1. Character Device Drivers………………………………………………………………………………………………….21 4.1.1. The file_operations Structure……………………………………………………………………………………21 4.1.2. The file structure…………………………………………………………………………………………………….22 4.1.3. Registering A Device………………………………………………………………………………………………22 4.1.4. Unregistering A Device……………………………………………………………………………………………23 4.1.5. chardev.c………………………………………………………………………………………………………………..23 4.1.6. Writing Modules for Multiple Kernel Versions…………………………………………………………..26 Chapter 5. The /proc File System……………………………………………………………………………………………………..28 5.1. The /proc File System………………………………………………………………………………………………………28 5.2. Read and Write a /proc File………………………………………………………………………………………………30 5.3. Manage /proc file with standard filesystem…………………………………………………………………………33 5.4. Manage /proc file with seq_file…………………………………………………………………………………………37 Chapter 6. Using /proc For Input……………………………………………………………………………………………………..40 6.1. TODO: Write a chapter about sysfs……………………………………………………………………………………40 The Linux Kernel Module Programming Guide i Table of Contents Chapter 7. Talking To Device Files…………………………………………………………………………………………………..41 7.1. Talking to Device Files (writes and IOCTLs)……………………………………………………………………..41 Chapter 8. System Calls…………………………………………………………………………………………………………………..50 8.1. System Calls…………………………………………………………………………………………………………………..50 Chapter 9. Blocking Processes………………………………………………………………………………………………………….55 9.1. Blocking Processes………………………………………………………………………………………………………….55 Chapter 10. Replacing Printks………………………………………………………………………………………………………….63 10.1. Replacing printk…………………………………………………………………………………………………………….63 10.2. Flashing keyboard LEDs…………………………………………………………………………………………………65 Chapter 11. Scheduling Tasks………………………………………………………………………………………………………….68 11.1. Scheduling Tasks…………………………………………………………………………………………………………..68 Chapter 12. Interrupt Handlers……………………………………………………………………………………………………….72 12.1. Interrupt Handlers………………………………………………………………………………………………………….72 12.1.1. Interrupt Handlers………………………………………………………………………………………………….72 12.1.2. Keyboards on the Intel Architecture………………………………………………………………………..72 Chapter 13. Symmetric Multi Processing………………………………………………………………………………………….76 13.1. Symmetrical Multi−Processing………………………………………………………………………………………..76 Chapter 14. Common Pitfalls……………………………………………………………………………………………………………77 14.1. Common Pitfalls……………………………………………………………………………………………………………77 Appendix A. Changes: 2.0 To 2.2……………………………………………………………………………………………………..78 A.1. Changes between 2.4 and 2.6……………………………………………………………………………………………78 A.1.1. Changes between 2.4 and 2.6…………………………………………………………………………………..78 Appendix B. Where To Go From Here……………………………………………………………………………………………..79 B.1. Where From Here?………………………………………………………………………………………………………….79

Creating Postbox in Exchange server 2013

Posted on June 8, 2015October 8, 2015 by coder

– Add User

Alias: Email Domain name @xxxxx.xx

Username : Email account username

Email – Policy : Automatically added by server which address is primary.

* We should change policy rule after adding, Permissions also need to be change.

Quagga Rip version 2 configuration

Posted on June 8, 2015June 26, 2015 by coder

# Change The RIP version to 2
telnet localhost 2602
Password:
ripd> enable
ripd# config ter
ripd(config)# router rip
ripd(config-router)# version 2
ripd(config-router)# exit

#------------------------------------------------------------
Quagga  zebra.conf
! -*- zebra -*-
! zebra sample configuration file
!
hostname ubuntu1404
password zebra
enable password zebra

! Interface's description.
!interface lo
! description test of desc.
!interface sit0
! multicast
! Static default route sample.
!ip route 0.0.0.0/0 203.181.89.241

interface lo
ip address 127.0.0.1/8

# client 1. ethernet 1 configuration
interface eth1
ip address 172.20.0.2/24
multicast

interface eth2
ip address 172.30.0.1/24
multicast

# eth3: e8:39 > 108_inet_3
# eth1: e6:cb > 108_inet_1

log file /var/log/quagga/zebra.log

# Change The RIP version to 2

telnet localhost 2602

Password:

ripd> enable

ripd# config ter

ripd(config)# router rip

ripd(config-router)# version 2

ripd(config-router)# exit

#------------------------------------------------------------

Quagga zebra.conf

! -*- zebra -*-

! zebra sample configuration file

hostname ubuntu1404

password zebra

enable password zebra

! Interface's description.

!interface lo

! description test of desc.

!interface sit0

! multicast

! Static default route sample.

!ip route 0.0.0.0/0 203.181.89.241

interface lo

ip address 127.0.0.1/8

# client 1. ethernet 1 configuration

interface eth1

ip address 172.20.0.2/24

multicast

interface eth2

ip address 172.30.0.1/24

multicast

# eth3: e8:39 > 108_inet_3

# eth1: e6:cb > 108_inet_1

log file /var/log/quagga/zebra.log

(Zebra) Quagga User manual

Posted on June 8, 2015June 19, 2015 by coder

Download from here : quagga.PDF_kutayzorlu.com

Components of Quagga (Zebra)

ospfd, implementing Open Shortest Path First (OSPFv2)
isisd, implementing Intermediate System to Intermediate System (IS-IS)
ripd, implementing Routing Information Protocol (RIP) version 1 and 2;
ospf6d, implementing Open Shortest Path First (OSPFv3) for IPv6
ripngd, implementing Routing Information Protocol (RIPng) for IPv6
bgpd, implementing Border Gateway Protocol (BGPv4+), including address family support for IP multicast and IPv6

Routingprozess	IPv4	IPv6	Telnet-Port	Routingprotokoll
zebra	x		2601	Zebra-Daemon
ripd	x		2602	RIP v1 und v2
ripngd		x	2603	RIP v3 (IPv6)
ospfd	x		2604	OSPFv2
bgpd	x	x	2605	BGPv4+
ospf6d		x	2606	OSPFv3 (IPv6)
isisd	x		2608	IS-IS

Page 39 of 858

« 1 … 37 38 39 40 41 … 858 »

Please Download file from here : CLICK >> lkmpg_kutayzorlu

Download from here : quagga.PDF_kutayzorlu.com