Very slow file upload on CF7 Form Submission

Question

I'm using the Contact Form 7 plugin in conjunction with the Contact form to DB plugin on my client's site to allow candidates to upload their CVs and my client to access submitted data via wp-admin.

When testing the Candidate Form and submitting a 5kb word document, it takes around 14 seconds for the file to upload and the user response to appear.

I've contacted the hosting company who say there are no issues with the server, so I'm assuming this must be an issue with the back-end code so my questions are:

1. What are the possible reasons for a file upload to take this long
2. What's the best method to troubleshoot such an issue on a live site.

Any pointers appreciated.

Answer 1

I just tried form bilbao, Spain and It took 3.45 secs.

I think It could be a routing problem, being the server in Canada it adds load time. Maybe from Hong Kong there are better routing connection to Canada, but Im just speculating.

To trobleshoot this you can use a Firefox´s plugin called Firebug "Net" mode, its shows all the calls to the server and the response and time taken to receive it. If it jumps to another page after sending the form press "Persist" to keep data in between page loads.

Im not very familiar to Chrome dev tools, but Im sure it also has a Network tool.