PHP odd string-related performance issue - php

Question

I have a class that is building some HTML using data stored in an array. There are around 100 items in this array. Each item includes information like company name, a description, and flags for the different programming languages the company supports. I am doing string concatenation as I build the HTML for each item.
I have noticed that performance suddenly takes a huge hit when I append the programming language data. I see the page rendering timer jump from 0.15 secs to ~0.60 secs. This time includes grabbing the same data from the database each time. I can consistently get the performance to jump between these 2 times but commenting/uncommenting the following line of code:
$html .= '<div class="programmingLanguages"><strong>Programming Languages</strong> '.implode(', ', $progLanguagesArray).'</div>';
I've also been able to get the same performance drop by appending a long test string, something like this:
$html .= 'testtesttesttesttesttesttesttesttesttesttesttesttesttesttesttesttest';
What's especially bizarre is that I have another line of code that uses the same 'implode' function and does NOT make any significant difference in performance:
$html .= '<div class="integrationMethods"><strong>Integration Methods:</strong> '.implode(', ', $intMethodsArray).'</div>';
Does anybody have any insight into what might be going on here? I am doing tons of concatenation like this elsewhere in my code and haven't seen anything like this before. At this point, I'm stumped.
Here's the full class:
class DeveloperView {
public static function getHtml($developers) {
$html = '';
$html .= '<div>';
$html .= '<div>';
$count = 0;
foreach ($developers as $developer) {
$url = $developer['attributes']['url'];
$phone = $developer['attributes']['phone'];
$company = $developer['attributes']['desc'];
$active = $developer['attributes']['active'];
$desc = $developer['object_value'];
$intMethodsArray = array();
if ($developer['attributes']['m1']) { $intMethodsArray[] = 'method 1'; }
if ($developer['attributes']['m2']) { $intMethodsArray[] = 'method 2'; }
if ($developer['attributes']['m3']) { $intMethodsArray[] = 'method 3'; }
if ($developer['attributes']['m4']) { $intMethodsArray[] = 'method 4'; }
if ($developer['attributes']['m5']) { $intMethodsArray[] = 'method 5'; }
$progLanguagesArray = array();
if ($developer['attributes']['dotnet']) { $progLanguagesArray[] = '.Net (C# or VB.Net)'; }
if ($developer['attributes']['asp']) { $progLanguagesArray[] = 'Classic ASP'; }
if ($developer['attributes']['cf']) { $progLanguagesArray[] = 'Cold Fusion'; }
if ($developer['attributes']['java']) { $progLanguagesArray[] = 'Java'; }
if ($developer['attributes']['php']) { $progLanguagesArray[] = 'PHP'; }
if ($developer['attributes']['perl']) { $progLanguagesArray[] = 'Perl'; }
if ($developer['attributes']['other']) { $progLanguagesArray[] = 'Other'; }
$html .= '<div class="';
if ($count % 2 == 0) {
$html .= 'listingalt';
} else {
$html .= 'listing';
}
$html .= '">';
$html .= '<div class="developerPhone">'.$phone.'</div>';
$html .= '<a class="ext_link" target="_blank" href="'.$url.'">'.$company.'</a>';
$html .= '<div>';
if (!empty($intMethodsArray)) {
$html .= '<div class="integrationMethods"><strong>Integration Methods:</strong> '.implode(', ', $intMethodsArray).'</div>';
}
if (!empty($progLanguagesArray)) {
$html .= '<div class="programmingLanguages"><strong>Programming Languages</strong> '.implode(', ', $progLanguagesArray).'</div>';
}
$html .= '</div>';
$html .= '<p>'.$desc.'</p>';
$html .= '</div>'."\n";
$count++;
}
$html .= '</div></div>';
return $html;
}
}

Answer 1

Now that I can provide an answer, I'll just post my follow-up comment as the 'answer'...
I did indeed have a 'bug' in my timer, in that it was calculating the end processing time AFTER the echo of the HTML. So the amount of data being sent to the browser was effecting the processing time, where I was expecting to see the time spent processing BEFORE transmitting any data.