Re: Individual bulk e-mails - performance question

Robert Cummings schreef:

On Sun, 2008-08-31 at 17:10 +0200, Jochem Maas wrote:

Robert Cummings schreef:

On Sun, 2008-08-31 at 12:12 +0200, Per Jessen wrote:

Robert Cummings wrote:

That's easily taken care of. Instead of a cron-job, you could have a script running as a daemon, checking for emails to be sent every 5mins.

That's the same as running a cron every 5 minutes except now you also need to detect if your daemon dies :) On the plus side though, you eliminate the overhead of starting up the script every 5 minutes :)

It is not the same as it will prevent multiple scripts running concurrently in case a batch of emails takes longer that 5 minutes. Checking if the daemon dies - I guess it's a matter of taste or paranoia, but I don't think it's necessary when the script is sufficiently simple: #!/bin/sh while true do

    <yourscript>
    sleep 300

done

I accomplish the same with cron scripts by using locks with expiry.

got an example? my cat skinning skills need to be improved, the cat won't like it but screw the cat, right?

<?php

    $lockName = 'myLockForSomething';
    $mLock = &$this->getService( 'lockManager' );
    if( !($lock = &$mLock->get( $lockName )) )
    {
        $age = $mLock->getAge( $lockName );
        if( $age > (60 * 60) ) // 1 hour
        {
            $mLock->forceRemoval( $lockName );
        }
    }

    if( !($lock = &$mLock->getRef( $lockName )) )
    {
        exit;
    }

    // Do stuff... current process has the lock.

    $lock->destroy();

?> Never really thought to until now... but I could easily roll the age check into the lock code itself and pass a parameter to the get() method. It would shrink the above code considerably.

proves tedd's adage that writing up a decent post always brings about some level of insight :-)

I implemented my own lock class which uses directory creation and the return value to determine if the lock was successful. Unlike file creation (or so I read several years ago) directory creation is atomic and works across NFS. As an added benefit, I'm able to store lock related data into the lock directory as files.

interesting, thanks for the feedback. I assume that this is coming from your interjinn lib, and that it's aimed at php4 (given the ampersands your throwing about) also your LockManager object seems to have a get() and getRef() method which do the same ... or is that typo?

Cheers, Rob.