I have a php script that updates a database. It takes round 5 minutes to complete. I want to set it to run automatically via cron job on cpanel but it don't execute via cron job.
Is there any time execution limit on cron jobs or is there any other effective way to automate this process on server?
set_time_limit() might help you
documentation
you can use supervisor to keep command line tasks running
I want to create a PHP script that will run non stop and execute some instructions every minute/hour (according to my need). It should never die.
How should I proceed to this one? How do I start the script itself?
What Iv'e done so far is created an infinite for loop and checking the time and if it's a new minute then calling my function. But when I call the link, it shows my browser is busy.
I want the script to run on Google Compute Engine without any need to call the URL from a second computer. I want something like android foreground service but for PHP.
Cron job is the answer.
Cron is basically a job scheduling daemon. It runs in the background and is executed automatically. You can set it to run at any time that you wish to. This nature of cron makes it useful for automating tasks.
A cron job, is a task which we carry out with the help of a cron.
So if you run a php script with the help of a cron, it'll run on the background. We don't need to run any infinite loops in the script. You can also set a cron job to run at specific time. How it is run and when it is run is totally upto how you configure the cron job. For that you have to edit the crontab file. A cron tab file is a text file containing a list of commands meant to be run at specified times and the commands in the crontab file along with their run times are checked by the cron daemon, which executes them in the system background.
Now, to create or edit entries in your own cron tab file:
$ crontab -e
Add an entry in the crontab file. One thing you have to remember is, for executing php scripts, use the php executable and call the php script from your crontab as shown in the example below
*/2 * * * * /usr/bin/php /var/www/html/project/cron-file.php
This reference might be helpful to you.
Hope this answer helps.
For Unix-system, best practice for such tasks is using Cron: https://en.wikipedia.org/wiki/Cron
Not only for PHP, but any periodical tasks.
My webserver is running cpanel and has a Cron job module in it providing a GUI to add/remove/edit cron jobs.
Problem: I need to create a large number of cron jobs (more than 100). Each cronjob simply does a wget <url> to trigger a bunch of PHP functions. What will be the best way to manage them? The current problem with cPanel's Cron GUI is that there will be no organization in the cron jobs. If I have 5 related cron jobs, added seperately admist 100 other unrelated cron jobs, it will get harder to find these cron jobs in the long list of cron jobs.
Should I stick to cPanel's GUI? Or is there an alternative GUI with better features like folders or the ability to move cron jobs up and down the list? Or should I just have 1 cron job, which calls a PHP file that does the various wget in PHP using CURL, with a table and stores the jobs in a MySQL database, essentially creating my own version of cron that runs off a single cronjob which triggers every minute?
Try grouping them.
Say you have 10 groups of ten, depending on how you organise them.
Each one of the cron jobs calls a PHP script that calls 10 other PHP scripts.
If you need them run at different times you could do a simple check with time() to see which scripts should be called.
You could call them the other PHP scripts using cURL.
Make sure to set a large script timeout though, or you might end up with lots of things going wrong.
Could you create one job in CPanel that will run one script.
Then in that script you could create the logic to run the 100 scripts.
If they are to be run at different times then you could use switch(time), or similar to manage execution.
Is it possible to schedule some tasks in php to run automatically on the server at a certain time of the day? . I heard abt cron jobs. is there any way to set it via php code
http://php.net/system lets you to run any command-line utility.
As for the certain command to set a cron job you have either to google a little or ask on serverfault.
I have a PHP script that needs to be run at certain times every weekday. Is cron or Windows task scheduler the only way to do this?
Is there a way to set this up from within another PHP script?
Depends how exact the timing needs to be. A technique I've seen used (dubbed "poor man's cron") is to have a frequently accessed script (a site's home page, for example) fire off a task on the first page load after a certain time (kept track of in the database).
If you need any sort of guaranteed accuracy, though, cron or a Windows scheduled task is really the best option. If your host doesn't support them, it's time to get a better one.
Apart from cron or Scheduled Tasks, you can have your PHP script to always run it. The process should sleep (within a loop) until the time has reached. Then, the process could execute the remaining functions/methods. Or, you can set up another script (which will act as a daemon) to check for the time and execute the other script.
Well since the web is a pull mechanism you have to have some sort of action that will trigger a PHP script to execute. cron is an option on *nix and task scheduler on windows. You could also write your own service that has a timer but only if needed, this is common on windows services for updaters, jobs etc.
One way you could do it is in the cron task just call a php script for each action needed. Or one php script that executes other tasks. The problem with web based tasks though such as PHP is timeouts. Make sure your tasks are under 60-90 seconds. If not you might look at using python , perl or ruby or even bash scripts to do the work rather than the PHP script.
cron seems like the best option for you though. You will have to call your script with wget. There are examples here: http://www.thesitewizard.com/general/set-cron-job.shtml
For instance this runs the script everyday at 11:
30 11 * * * /usr/bin/wget http://www.example.com/cron.php
Cron, of course, is by far the best way to schedule anything on *nix.
If this is in a remote server you do not have cron access to, you can setup cron/windows scheduler on your computer, to open a web browser to the page that contains the script you wish to run
You probably want to use cron (or windows scheduled tasks).
If you really wanted, you could set up another php script to run continuously with an infinite loop (with a sleep command inside the loop, say for 30 seconds or so) and then when you reach your desired day/time execute the other script via a shell command call. While possible, I can't think if a single good reason to use this method rather than cron/scheduled tasks
You can write a long running script that runs your main script in predefined times but it will be very unnecessary, error prone, and it will basically be a "cron rewrite in phph".
Using the real cron itself will be easier and a more robust solution. If you are packaging an application, you can put a file in /etc/cron.d which contains a single cron line running your application.
You'll need to use a cron job (under Linux/Unix) or a scheduled task under Windows. You could have another script running on a continuous basis which checks the time and executes a script at a specified interval, but using the OS-supplied mechanism is easier to manage and resilient to restarts, etc.
The Uniform Server project has some good suggestions on mimicking cron in environments where cron is unacceptable. Still though, if cron is at all an option, use it.