increasing the browser width and height on EC2 Test Agent

Hi Fellow webpagetesters,

I am trying to find if it is possible to increase the height/width of the browser on the EC2 Test Agent (private), so i can get larger screen captures of web pages. (We have a private instance of the WPT server and agent)

I looked at the urlBlast.ini and there are settings:
browser width=800
browser height=600

can I set these as part of user data string?

Currently the browsers are forced to run at 1024x768. The Chrome and Firefox agents can be told to change the browser size on a per-test basis using the setViewport command but there is no way to change it globally. The code also sets the desktop resolution on the EC2 agents to 1024x768 so there are a couple of changes that would need to be made to the code to make it possible (it is all doable, the code just doesn’t support it right now).

Thanks for the quick reply.

I’d like to suggest upping the default resolution for testing to 1366x768 or 1280x800 which are now pushing past 1024x768.

Would this make the new speedindex metric a little more realistic? Most designs fit within 1024 and the same assets are used to render the above the fold area so I guess there shouldn’t much change in speedindex unless you move to a height that increases the “fold” and shows more content down the page.

The EC2 video drivers don’t support a screen resolution higher than 1024x768 for 24-bit (and I can’t run WPT at lower bit depths). The latest version of the agent code tries to set the desktop resolution as high as possible (up to 1920x1200) and all of the public agents that aren’t on EC2 can do the resolutions you mention but EC2 just can’t.

I did some poking around to see if there were other video driver options for Xen (what EC2 runs on) but from the looks of it Amazon would need to run the instances with more virtual video memory and given the usage model of their service it probably doesn’t make sense for them.

Hi Pat has this been changed in the end? still being limited to 1024 on ec2 via strange thing from the UI works??

The Linux agents can go up to 1920x1200 on EC2. Windows is up to 1280x1024.

Thanks for the prompt reply Pat, is very strange…

We’re using an aws autoscale setup with min=1 and max=5 instances and test triggered via a cron job and and for these tests where the setVieportSize scripting command is set I keep getting sporadic timeouts
ERROR: Error creating WebPageTest result

I’ve even forced an agent updated (putting the unzipped files into the master /work/update) but nothing has changed.

Looks like is happening when i force a viewport bigger than 1024, any idea on what is going on? I’ve even tried the default_viewportzise setting but have got a similar behaviour.

If it works from the UI then the most likely cause is that is sending the script to the API incorrectly. If it isn’t urlencoding the script that would certainly cause it.

The “TIMEOUT” messages also look like they are specific to and I’m not sure how that gets set. If it is giving up on the test before it gets a chance to run because the instances haven’t started yet that could also explain it.

not sure because it doesn’t work from the UI neither

i think that json error comes from the wpt nodejs wrapper api

also i’m not getting any timeout from many other similar tests (not passing the view port size command) which kind of exclude the instance not started problem which i thought by using the min=1 shouldn’t happen anyway

Hi @Patrick I’m still being impacted by this issue… and is pretty annoying as is screwing all our performance monitoring, i’m sure our ec2 agents are running the latest wpt version and with a setViewportSize \t 1025 \t 768 everything is smooth but as soon as i increase that to something bigger e.g. 1280 i start to get missed runs or timeout errors.

Never heard about this?
actually had to switch to a windows box surprised there’s no fix for the display driver limited to 1024…