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

Get Total From While Loop
I'm trying to get the total for each product and add them for a Grand Total to list outside the loop

Show message after entering data
Hello Colleagues

I would like to display messages after entering the data example: "
dat

help countdown timers
hello every one,

I'd like to know how to insert many countdowns in the same page.
The dura

First root of a number
Hi,

I can't find any function in php to give me the first root of a number.
Is there any

update sql when refresh - php
hi
I have made a table (attachement)

the users can update the sql database using + or x bu

Need help to identify this error please
:confused:Can anyone help me tell what this error message means? Maybe tell me where to look to fix

How do I send data using an html link
Hi

If I have
<a href="main_file.php">

How do I send data t

downloading a file as HTML
Hi.
I'm rather confused with forcing a download. I just want to save dynamic content (from $_SESS

Google Wave
So... has anyone used it yet? Is it any good?

http://wave.google.com/help/wave/about.html#vid

PHP Upload issue
Hi guys,

I have stumble across an interesting issue with my script and is doing my head in.