What potential issues could arise when using PHP for mass email sending?

One potential issue when using PHP for mass email sending is that it can overload the server and cause performance issues. To solve this problem, you can implement a queue system to send emails in batches, rather than all at once. 

// Example of sending emails in batches using a queue system

// Define the batch size
$batchSize = 100;

// Get the list of email addresses to send to
$emails = array('email1@example.com', 'email2@example.com', 'email3@example.com', /* more email addresses */);

// Split the email addresses into batches
$emailBatches = array_chunk($emails, $batchSize);

// Loop through each batch and send the emails
foreach ($emailBatches as $batch) {
    foreach ($batch as $email) {
        // Send email code here
    }
}

Keywords

SMTP mail function spam filters rate limiting bounce handling

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