Capturing Dev Tools Timeline hangs at fetching the result for some pages

[kzarifis]

I think I have an idea what's up, seems like something was hanging while trying to fetch the timeline indeed.

I saw the following in /var/log/apache2/error.log:
"PHP Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 72 bytes) in /var/www/webpagetest/devtools.inc.php on line 1008"

Adding
ini_set('memory_limit', '256M');
at the top of devtools.inc.php seems to have fixed it. I'm not 100% this is the right solution or if there's an underlying issue, but it does look like the issue happened more often for larger pages (>130 requests, => larger timelines), so it does seem like just a matter of needing more memory than the default 128M. Didn't snoop around the code much to see of using 128M is justified, but I was convinced that it was when I manually fetched a timeline for one of the pages I was testing and saw that it was 62M (!)