SteamVR Performance graph - how to interpret?

[Godrik Underscore]

I understand what the green and the yellow lines mean, ie meeting the frametime/ yellow is when reprojection kicks in.

Red I believe is a dropped frame but I have no clue what the purple line means.

[tpo88]

i have never seen purple... :S

[Rectus]

Not sure, but it seems to indicate some kind of prediction failure or unexpected performance drop.

The separate advanced performance graph is documented here at least:
https://developer.valvesoftware.com/wiki/SteamVR/Frame_Timing

[Godrik Underscore]

This is what they look like (not my pic tho).

https://imgur.com/a/Uch7sp3

[Badclockworkz]

It means the frame has been reprojected if you havent gotten to the answer yet!

[Rectus]

Originally posted by Badclockworkz:

It means the frame has been reprojected if you havent gotten to the answer yet!

A purple line doesn't mean that. It's some kind of failure state.

Orange lines mean mean that a previous frame is reprojected once. Yellow is the same but with Motion Smoothing enabled. Red means the frame has been reprojected multiple times.

[MosesPoe]

Isn't purple when you reach a performance bottleneck? Either your CPU or GPU isn't keeping up depending on what the game is more demanding on. FPSVR will give you a better break down of performance or lack there of https://store.steampowered.com/app/908520/fpsVR/ once you nail down the issue, it's best to turn FPSVR off as it does impact performance slightly.

[Rectus]

I mean, if you reach a performance bottleneck, SteamVR will normally still reproject the last complete frame, giving you yellow, orange or red lines. Guessing purple might be any time when it stalls out completely, can't reproject the frame, and just redisplays the last frame as-is.

[aaron.leiby]

Purple (magenta) means the SteamVR compositor failed to present a new frame for some reason, so it was unable to perform any form of reprojection, resulting full screen judder.

[MosesPoe]

Originally posted by aaron.leiby:

Purple (magenta) means the SteamVR compositor failed to present a new frame for some reason, so it was unable to perform any form of reprojection, resulting full screen judder.

Is there a resource somewhere that has a full break down and explanation?

[aaron.leiby]

There is a mouse over tool tip. There is also the wiki page linked above that covered the advanced frame timing graph that has a more detailed breakdown.

[MosesPoe]

Originally posted by aaron.leiby:

There is a mouse over tool tip. There is also the wiki page linked above that covered the advanced frame timing graph that has a more detailed breakdown.

Google search isn't what it used to be, didn't even know there was a Wiki page for it. You search things about SteamVR, and it's an endless list of people not knowing what they are talking about. *Edit* I should say that of the things needed for VR, SteamVR is the one thing I've had the least issues with personally.