There are 3 commands that we can use sar top mpstats You may need to install sysstat package to use these commands : apt-get install sysstat If you install sysstat , enable systat by edit: nano /etc/default/sysstat    -> change ENABLE from false to true.Read More →

My OS crash today and i had to reinstall mysql server. I am using Windows 2003 (quite old  😉 There are a few things happen when i reinstall the mysql , and it happens at the “instance” configuration step. 1. Canot find my-template.ini , => Fix: copy my-template.ini to bin/ directory 2. Can not start service It’s because the mysql path in Services is not correct : C:\Program Files\MySQL\MySQL Cluster 5.5\bin\bin\mysqld” –defaults-file=”H:\Program Files\MySQL\MySQL Cluster 5.5\bin\my.ini”  MySQL => open registry , go to HKLM \ System\Current Control Set1\ Services Locate mysql , and update the path => Try to restart , if you still can notRead More →

Svnx doesnt have interface to switch the svn repository from one url to another. If you change your url , or move your repository to a new url you can do this. Open the terminal Using “cd” command to go to your repsoitory , e.g. cd /Users/yourname/websites/abc.com (abc.is your svn) then run the command svn switch –relocate old_url new_url if you want to check your old url , you can run the command “svn info”Read More →

DriverIdentifier is a desktop/webapp hybrid—install the program then launch it to scan your system for all device drivers then the program checks to see if there are new drivers available for your hardware on the web and these results are displayed in a browser tab. Any needed driver updates can be directly installed by clicking on the Update link. The program is relatively straightforward. Running it on my Lenovo laptop resulted in a handful of drivers that need updates such as my webcam, graphics card, and SATA controller. Clicking on the update link takes you to a page with several mirror sites from which youRead More →

Today, my server is out of disk and i see there are lot of files in /tmp , their names are phpXXXX , i know these  files are uploaded by PHP, but why they are not deleted after the scripts end. After a lot of troubleshooting , i found that there is some errors in my apache error log with “child process exit , filesize limit…” i did some research , and found that it’s because apache can not  work with file larger than 2GB , i searched though my file system and saw there are some of my application logs files generated files atRead More →

When you think your mysql is slow , the first step is to analyze your sql query with “Exlain” command. This is an example explain select * from table1 inner join table2 on table1.field1=table2.field2 and table.field3 =577458498 It will give you some thing like this , look at the “rows” column , if the number of that column is too high, try to reduce it by changing your query , or add index. +——–+——+——————-+———+———+——-+——+———–+ |table | type | possible_keys | key | key_len | ref | rows |Extra | +——–+——+——————-+———+———+——-+——+———–+ |employee| ref | surname,surname_2 | surname | 41 | const | 1 |where used |Read More →

Today I found that Apache on my server was very slow and a lot of child pid xxxx exit signal File size limit exceeded (25) errors in error_log. It turned out that one of my applications log files are 2GB. WHen apache process read a file over than 2B it will give that error. It could be apache logs or applications log How to fix it? Let start by searching your apache logs find /var/log/apache2 -type f -size +20000k -exec ls -lh {} \; | awk ‘{ print $9 “: ” $5 }’ If you still can not find the large files – search theRead More →

If I’m ever wondering how long my PHP scripts take to execute, I add this code to the start of my pages: <?php function getTime() { $a = explode (‘ ‘,microtime()); return(double) $a[0] + $a[1]; } $Start = getTime(); ?> Then I add this to the end of my script: <?php $End = getTime(); echo “Time taken = “.number_format(($End – $Start),2).” secs”; ?> Sometimes it’s good to get hard figures on how long your script takes to execute, particularly with complex MySQL queries. If your script is particularly tardy and you want to find out where the blockage occurs, you could also try moving the $Start or $End lines to different parts of the script to measure the execution speed of each section.Read More →