3 Step to keep track OS memory usage by process


So many people asking how to keep track on the OS memory usage by process, as you know a bit about Physical Memory, Virtual Memory (VSZ), Resident Set Size (RSS), Shared Memory, Paging Memory…etc, counting RSS to determine memory usage is very common way and easier to understand for dummies like me, although it’s not a precise figure while you’re ignoring shared memory, fs cache..etc.
But anyway this tutorial is starting point to help you monitor the process RSS usage and keep tracking the usage that allows to identify peak/min.

Alright, you need to create one database or table, and one script and one cron job.

Step 1 – Create a database for storing stat data

GRANT INSERT, UPDATE, DELETE, SELECT on sysstat.* to sysstat@'localhost' identified by 'passw0rd';
USE sysstat;
CREATE TABLE 'memory' (  'id' int(11) NOT NULL auto_increment,  'date' datetime NOT NULL,  'memory' int(20) NOT NULL,  'process' varchar(300) NOT NULL,  PRIMARY KEY  ('id')) ENGINE=MyISAM AUTO_INCREMENT=21794 DEFAULT CHARSET=latin1;

Step 2 – Script


To show all memory usage by process

./memory_stat.sh usage
[root@vm1 sbin]# ./memory_stat.sh usage
2011-05-01 01:55:39 16576 /usr/lib/courier-imap/bin/couriertls
2011-05-01 01:55:39 35576 /usr/lib/courier-imap/bin/imapd
2011-05-01 01:55:39 38832 /usr/sbin/httpd.worker
2011-05-01 01:55:39 73100 MailScanner:
2011-05-01 01:55:39 125632 clamd
2011-05-01 01:55:39 208964 /usr/libexec/mysqld
2011-05-01 01:55:39 429720 /usr/bin/php-cgi

To record into database

./memory_stat.sh record

To retrieve the usage report

./memory_stat.sh report {process} {date - optional} 
[root@vm1 sbin]# ./memory_stat.sh report php "2011-05-01 01"
php usage report on vm1.dreamerworks.net
date	memory
2011-05-01 00:00:01	471588
2011-05-01 00:05:02	468772
2011-05-01 00:10:02	470788
2011-05-01 00:15:01	471392
2011-05-01 00:20:01	472140
2011-05-01 00:25:01	469016
2011-05-01 00:30:02	469016
2011-05-01 00:35:01	469016
2011-05-01 00:40:01	472376

To housekeep the database

./memory_stat.sh housekeep



process=`ps aux|awk '{print $11}'|sort|uniq|grep -v -e grep -e awk -e ps -e sort -e uniq`
date=`date +%Y-%m-%d\ %H:%M:%S`

for PS in $process; do

echo "$date `ps aux | grep -- $PS |grep -v grep | awk '{sum +=$6}; END {print sum}'` $PS"


record() {
usage > /tmp/usage.log
mysql -u$dbuser -p$password <<EOF
use $database;
`while read date time memory process;
echo "insert into memory (date,memory,process) values ('$date $time','$memory','$process');"
done < /tmp/usage.log

rm -f /tmp/usage.log


housekeep() {
mysql -u$dbuser -p$password <<EOF
use $database;
delete from memory where date < CURRENT_DATE - $housekeepday;

report() {
if [ x$1 = "x" ];then
        echo "Usage: $0 [process]"
datetime_arg="AND date like '$2%'"
echo "$process usage report on `hostname`"
mysql -u$dbuser -p$password <<EOF
use $database;
echo "select date, memory from memory where process like '%$1%' $datetime_arg order by date";


case $1 in
	usage | sort -k 3n
	report $2 $3
        echo "Usage: $1 (usage|record|housekeep|report [process] [date])"

Step 3 – Cron Job

crontab -e
0,5,10,15,20,25,30,35,40,45,50,55 * * * *       /usr/local/sbin/memory_stat.sh record

That’s it

At least, you may tell a bit more about which process is huger one and then you’ll able to narrow down for investigation.

Rename Post format string in WordPress theme


Because post format string is hard coded in post.php, so you can’t change them in filter way. To rename the post format string and display in a theme, you can add the following function in function.php.

function post_format_nicename() {
		global $post;
		$slug = str_replace('post-format-', '', get_post_format($post->ID));
		if(empty($slug)) {
				$slug = 'standard';
		$source = array('Standard', 'Status');
		$replacement = array(__('Blog Post', 'textdomain'),__('Status Update','textdomain'));
		$strings = str_replace($source, $replacement, get_post_format_strings());
        $string = $strings[$slug];
		return $string;

To display the mod-ed post formant name, call this function

echo post_format_nicename();

How to filter “Standard” Post format in WordPress

Post format

As you know Post Formats is a theme feature introduced with Version 3.1. A Post Format is a piece of meta information that can be used by a theme to customize its presentation of a post. The Post Formats feature provides a standardized list of formats that are available to all themes that support the feature. There are new template tag to play with post_format as below

WordPress Codex

However, when you try to implement post_format, usually you’ll try to sort out the posts for each formats. For example, show all images format.

<a href="<?php echo get_post_format_link('image');?>">
Show Image Posts

The above code do present a link taking you to post_fomart archives page, pretty easy right? So… how about display the standand post? Unfortunately, there is no out of box function to do that. Let’s work it out.


Setup theme support in functions.php, I put the post formats in vars, because we need to reused them in some place within the theme. Additionally, I created another function to register query variable to handle new query for standard post format.

/* Register Query Variables*/
add_filter('query_vars', 'my_queryvars' );
function my_queryvars( $qvars )
$qvars[] = 'filter';
return $qvars;
/* Post formats support */
$my_post_formats = array( 'status','aside','image', 'gallery', 'link', 'video', 'audio' );
foreach ($my_post_formats as $shortname) {
	$my_post_formats_longname[] = 'post-format-'.$shortname;
add_theme_support( 'post-formats', $my_post_formats );

The filter links

<a href="<?php echo add_query_arg( 'filter','standard',remove_query_arg('post_format'));?>"><?php echo get_post_format_string('');?></a>
<?php global $my_post_formats; foreach ($my_post_formats as $postformat) { ?>
	| <a href="<?php echo get_post_format_link($postformat);?>"><?php echo get_post_format_string(str_replace('post-format-', '', $postformat) ); ?></a>
<?php } ?>

the loop

Put the following code before the loop. This is a new taxonomy query since WordPress 3.0, it allows you to setup own query by taxonomy terms. And you may notice that I’ve put “NOT IN” operator to filter out standard posts. It is because “standard” post do not have post-format- taxonomy. The first condition to determine the from the $_GET request.

<?php if(get_query_var('filter') == "standard") { 	global $my_post_formats_longname; 	$args = array( 			'tax_query' =--> array(
			array( 'taxonomy' => 'post_format',
				  'field' => 'slug',
				  'terms' => $my_post_formats_longname,
				  'operator' => 'NOT IN'
	query_posts( $args );

That’s it

Btw, I hope there have a better solution in future WordPress release. Thanks for reading!

Submitting WordPress post from frontend without a plugin

Screen Shot
Screen Shot


This tutorial will guide you to create your own custom post composing form to enable fast blogging with your favorite theme without adding a plugin. I’m looking for any alternative to not porting P2, however…. none.,  finally that’s the reason i wrote it, and It was also inspired by the original development from http://wpshout.com/wordpress-submit-posts-from-frontend/.


I found the code from http://wpshout.com/wordpress-submit-posts-from-frontend/ , but it doesn’t  handle file attachment, indeed most people and I was demand on image uploads for status update,  photo blogging.. whatever . But to get working with build-in WordPress media upload function require a lots of code work,  and if you prefer a fully functional media library, you could base on P2 theme instead.

How it work

  1. It create a post form to allow  the post content inserted by wp_insert_post.
  2. following the post_id, it attach the uploaded files to the post.
  3. Set the first ordered image to the post “featured images”
  4. Lastly, you call get_all_thumbnails before the_content() in order to retrieve the uploaded files.


The critical limitation is lack of media features, unlike build-in media library, you can customize your post images and place it on your desired position. Therefore the images only able to retrieve by the_post_thumbnail() for single image or get_all_thumbnails() for multiple images.

Continue reading “Submitting WordPress post from frontend without a plugin”

jQuery imgpreview undefined object issue

When the imgpreview.js and the loader script load in every page header, sometime maybe your page didn’t have any image class for display a image preview. A warning or error message will appear in your browser. How to avoid the error?

Open imgpreview.js

Append the code.

if (!h.length) return this;

after this line

h = this.filter(':linkingToImage(' + b.srcAttr + ')');

Look like

h = this.filter(':linkingToImage(' + b.srcAttr + ')');if (!h.length) return this;

loader.js loader script example.

var $imgprv = jQuery.noConflict();
$imgprv(document).ready(function() {
    $imgprv('.pic a').imgPreview({
    containerID: 'imgPreviewWithStyles',
    srcAttr: 'rel',
    imgCSS: {

    onHide: function(link){
        $imgprv('span', this).remove();


CSS min-height headache?

Assuming you do know how min-height is ’supposed’ to work, but somehow it doesn’t (Thanks Microsoft), here you can try to incorporate with “height:auto !important;” together.

content {
  height:auto !important;