Use a custom php.ini with mod_php or php as a cgi

Describes in exhaustive detail how to change configuration settings and implement a custom php.ini file for use with the Apache Web Server.

PHP run as Apache Module (mod_php)

Add this to your root .htaccess file. Say your php.ini is in folder /askapache.com/ini/

SetEnv PHPRC /askapache.com/ini

Caching Techniques for Apache .htaccess Gurus

This article shows 2 awesome ways to implement caching on your website using Apache .htaccess (httpd.conf) files on the Apache Web Server. Both methods are extremely simple to set up and will dramatically speed up your site!

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Apache .htaccess caching code

# 1 YEAR

Header set Cache-Control "max-age=29030400, public"

# 1 WEEK

Header set Cache-Control "max-age=604800, public"

# 2 DAYS

Header set Cache-Control "max-age=172800, proxy-revalidate"

# 1 MIN

Header set Cache-Control "max-age=60, private, proxy-revalidate"

For fail-safe code implement this to the above

# any Expires Directives go here



# any Header directives go here

At least one of the 2 modules needs to be built into Apache; although they are included in the distribution, they are not turned on by default. To find out if the modules are enabled in your server, find the httpd binary and run httpd -l; this should print a list of the available modules. The modules we're looking for are mod_expires and mod_headers.

If they aren't available, and you have administrative access, you can recompile Apache to include them. This can be done either by uncommenting the appropriate lines in the Configuration file, or using the -enable-module=expires and -enable-module=headers arguments to configure (1.3 or greater).

Complete Article

Becoming PHP 6 Compatible

In a new post on 'Making the Web blog', there's a new post that talks about preparing your code for PHP6 when it comes around. "If you want to make use of PHP 6 when it comes, you're going to have to write your new scripts so they are compatible, and possibly change some of your existing scripts. To start making your scripts PHP 6 compatible, I've compiled a list of tips to follow when scripting." The list of tips has five entries:

• Don't use register_globals
• Stop using magic_quotes
• Don't Register Long Arrays
• preg instead or ereg
• Don't initiate objects with the reference operator

How to turn a php script to an exe..for free

There is an interesting article in jaslab go through this article Click here.

Measuring the effective bandwidth of your users

Its Sample javascript implementing this.. Just go through this article

http://www.die.net/musings/page_load_time/

How to find slow mysql queries?

By Justin Silverton

It has happened to all of us running a website or application using mysql as its back-end database. Performance is suddenly very sluggish and you have no idea what is causing it. Now there may be other factors that are causing the issue (overloaded CPU, harddrive running out of space, or a lack of bandwidth), but it could also be a query that is not optimized and/or is taking much longer than it should to return.

How do you know which queries are taking the longest to execute? Mysql has built-in functionality for checking this through the slow query log.

To enable (do one of the following):

1) add this to /etc/my.cnf

log-slow-queries=/tmp/slow_queries.log
long_query_time=10

2) call mysqld with –log-slow-queries[=/tmp/slow_queries.log]

long_query_time is the maximum amount of seconds a query can take before it will be logged to the slow query log.

other related options:

–log-slow-admin-statements

Log slow administrative statements such as OPTIMIZE TABLE, ANALYZE TABLE, and ALTER TABLE to the slow query log.

–log-queries-not-using-indexes

If you are using this option with –log-slow-queries, queries that do not use indexes are logged to the slow query log.

If slow query logging has been enabled successfully, you will see “ON” in the VALUE field for “log_slow_queries” (shown above).

Note: Queries handled by the query cache are not added to the slow query log, nor are queries that would not benefit from the presence of an index because the table has zero rows or one row.

You may also run into the case where a query is slow at one time (such as when you are logging it) but not another (if you execute it manually):

* A table may be locked, causing the query to wait. the lock_time indicates how long the query waited for locks to be released
* none of the data or indexes have been cached in memory. This is common when MySQL first starts or your tables have not been optimizied
* a background process was running, making disk I/O considerably slower
* The server may have been overloaded with other unrelated queries at the same time, and there wasn’t enough CPU power to do the job efficiently

Log analysis

MySQL also comes with mysqldumpslow, a perl script that can summarize the slow query log and provide a better idea of how often each slow query executes.

sorttable: Make all your tables sortable

Do you want to sort the tabular data?

Follow the Link.

How to add keyboard shortcuts to your website

By Justin Silverton

The following javascript code will allow you to add keyboard shortcuts to any webpage.

The code

(put this on any page where you want keyboard shortcuts)

I can't put the HTML code please refer:- Html Code

(put this in a file called shortcut.js and upload to the same directory as the webpage with the above code). This example will display an alert message when the escape key is pressed.

function keyShortcut() {
var e = window.event;
var code = e.keyCode;
if (code == 112) { //checks for the escape key
alert('escape key pressed');
}
}

The following are some more keyboard codes that can be used within the above script (in the if code == X, where X is one of the codes below).

key	Code
tab	9
enter	13
leftwindow key	91
right window key	92
f1	112
f2	113
f3	114
f4	115
f5	116
f6	117
f7	118
f8	119
f9	120
f10	121
f11	122
f12	123

PHP Optimization Tricks

There are a number of tricks that you can use to squeeze the last bit of performance from your scripts. These tricks won't make your applications much faster, but can give you that little edge in performance you may be looking for.

1.When incrementing or decrementing the value of the variable $i++ happens to be a tad slower then ++$i. This is something PHP specific and does not apply to other languages, so don't go modifying your C or Java code thinking it'll suddenly become faster, it won't.

2.When working with strings and you need to check that the string is either of a certain length you'd understandably would want to use the strlen() function. But Calling isset() happens to be faster then strlen() because unlike strlen(), isset() is a language construct and not a function meaning that it's execution does not require function lookups and lowercase. This means you have virtually no overhead on top of the actual code that determines the string's length.

Ex.
if (strlen($foo) <> 1, "oranges" => 1, "mangoes" => 1, "tomatoes" => 1, "pickles" => 1);
if (isset($keys['mangoes'])) { ... }

The bottom search mechanism is roughly 3 times faster.

9.file including and requiring.

First, you should only use require if you KNOW you will need that file on that page. If you MIGHT use it, use
include instead because PHP opens up all files that are required, whether the script gets there or not. To help out the programmer,
I suggest using "include_once" and "require_once".

Second, get your source file sizes as small as possible and only include/require files you absolutley must have.
If you only need one function in a file, consider breaking that function into its own file. I found on my system
that for every KB of source code that was included/required, I lost one transaction per second (tps). This may
not lead to perfectly organized code, but if speed is a concern, it is definitley worth it.

10.true is faster than TRUE
How come true is faster than TRUE?
This is because when looking for constants PHP does a hash lookup for name as is. And since names are always stored lowercased, by using them you avoid 2 hash lookups.

11.Perl-regexps are faster than POSIX-regexps
http://www.oreilly.com/catalog/regex/ This books explains regex and why a posix regex is slower.

12.FOR vs. WHILE vs. DO-WHILE
just out of curiosity I wanted to see which one of these structures are faster. I believed that "for" will be the fastest but the tests proved I was wrong.

for: 2.078712940216064
while: 1.981828927993774
do: 1.936743974685669

For 2,000,000 iterations the do-while structure is almost 0.15 seconds faster than the for structure. This won't mean very much for small sites but in complex application where you'll have to handle many hits it will make a difference.

13.Here are two tips for loops. If the number of iterations in a loop is low, you might get some performance gain from replacing the loop with a number of statements. For example, consider a for loop that sets 10 values in an array. You can replace the loop with 10 statements, which is a duplication of code, but may execute slightly faster.

Also, don't recompute values inside a loop ex:- count(arrname) .The price for coding in this style was a slight hit in performance, as the loop calls the count function repeatedly.

If you know or have any additional optimization tricks let me know.

References:-
http://ilia.ws/archives/12-PHP-Optimization-Tricks.html
//Zend

How to use MySQL REPLACE function

Here’s a MySQL query fuction that’s easy to forget about: REPLACE. Let’s say I have a bunch of records in a field with http://www and want to quickly change all to http://. Here’s the syntax to update:

UPDATE tdurl_1 SET URL = REPLACE(URL, ‘http://www.tdurl.com/’,'http://tdurl.com/’);