Sequencing or queuing parallel process

Posted on 16th Feb 2014 07:03 pm by admin

Scenario is as follows
There is one parent process say P1 and 4 child processes say A B C D

Process A starts at 3:00 pm
Process B starts at 3:15 pm
Process C starts at 3:30 pm
Process D starts at 3:45 pm

Process A take 1 hour for completion and process B,C,D takes 10 mins for completion
At a time only one process is allowed to execute since these process shared some common resources so at any point of time only one process is allowed to execute. but these are scheduled job so process B, C, and D must wait till process A get completes

so process B must wait till 4:00 PM for execution
and starts at 4:00 PM
process C must start at 4:10 PM after completion of process A and B
process D must start at 4:20 PM after completion of process A and B and C
so these sequencing also should maintained

B, C and D cannot start unless and until A is get completed and user dose not know
How much time A will take so B,C and D must wait for completion of A and after A completes then and then only B,C and D execute in a same order

so how to implement wait mechanism for this scenario?

Currently i have implemented a lock mechanism where first process A will create a lock file and process B,C and D will continuously poll this lock file and as soon as process A finishes it will release a lock on and whichever process acquires a lock first will get executed first but here sequencing is not maintained and process executes randomly

so what kernel objects like event, semaphore are needed to solve this scenario.

please help to solve this scenario of process waiting for execution in a queue.

-Thanks

Your Answer:

Login to answer

Other forums

utf8_general_ci error ??
I have all kinds of data to be inserted in database table

//I am getting this error

Yo

Why doesn't this work? (SSH2)
This is my script:

Code: <?php
$connection = ssh2_connect('213.251.167.109', 22);

present value of sequence?
Hi

Please help me to find out the present value of sequence?

Thanks

Multiple Pages
Hi. Im very new to php. I'm trying to create a basic login/registration page.

So I have a bas

Problem!
I have another problem, when i run this code i get this error "Parse error: syntax error, unexp

Getting rid of quotes when printing data
Hi Guys, I use the filter_var FILTER_SANITIZE_STRING to filter the textarea input. The function esca

ctype() validation - allowing illegal characters
Hello,
I use ctype() to filter and validate a user form. However, I am trying to allow certain c

upload photo limits
ive got a upload photo script and im just trying to make more secure currently it limits size and as

PHP If Else statement for breadcrumb
Hi

I am trying to use a PHP if else statement to display a breadcrumb link on wordpress

Formatting echo from database
So I have a database that stores First and last names, then echos them back to a website, as of now