greenenemy wrote: ↑30 Oct 2022, 07:48
Wouldn't that be just visible as stutter or low fps?
Yes and no.
It depends on the mathematical variables.
Depends on how big the clumped the thread-thrash chained-freezes are (e.g. 1.5ms freezes in a driver) and how frequent they are.
IF (the microfreezes are regular/cyclic) AND (they are sufficiently big in milliseconds) THEN it can becomes visible stutter (or extra blur).
Don't forget that there's a stutter-to-blur continuum (
www.testufo.com/eyetracking#speed=-1 ...stare at 2nd UFO for 30 seconds to understand). Stutters and persistence blur is essentially the same thing! Like slow vibrating music strings (shaky) versus fast vibrating music strings (blurry).
Rapid jitters = extra persistence motion blur above-and-beyond display's lowest persistence capability. Like a fast vibrating guitar string looks blurry.
Microstutters are only easily visible when the stutter jump (stutter error in millisecond) exceeds the motion blur (in persistence milliseconds). If they're just occasional one-off minor microstutters, they may not be visible in the motion blur of low frame rates (e.g. 3ms stutter in 20ms MPRT), they may not be visible stutter but still create a "It Feels Off" effect. Now, 3ms stutter in 3ms MPRT is much more visible (3ms is bigger than a single framedrop at 360fps 360Hz on a 360Hz monitor is more human visible than a 3ms microstutter at 30fps on a 60Hz LCD with its 16.7ms refreshtimes).
Oftentimes, the refresh rate race, with higher frame rates, massively amplify visibility of small problems. As the refresh rate race pushes the Hz, the gradually unpeeled stutter onion (of multiple stutter/microstutter causes) reveals ever-tinier human visible problems.
Other times, it's a "I feel like I'm performing worse but I don't know why" situation. Allow me to explain why:
Just like an Olympics 100 meter sprint, two racers may finish almost simultaneously (1ms apart) and not know who won, until they see the electronic scoreboard. If your gunshot is 1.5ms delayed and both of you have identical human reaction time (e.g. both averaging 175ms), then the one with the less delay is more likely to get the frag. You don't always notice except you notice your scores are lowering. It could be simply an aim stabilizer fail (e.g. overshoot/undershoot by 1.5ms) or a buttonpress erraticness (button reacts 1.5ms later than usual), that you don't really feel but it feels like you're underperforming.
Likewise, the same situation happens with two FPS players suddenly seeing each other simultaneously and shooting each other simultaneously -- with the same human reaction time. In this situation, that millisecond is an advantage even if you don't feel the millisecond until after the frag has already happened. If you start suddenly playing badly and don't know why, it's often common for the esports player to suspect latency-change effects -- to legitimate reason. Since it's a race-to finish situation. Not all studies successfully eliminate error margins to successfully test these factors surgically.
See
Millisecond Matters: The Amazing Human Visible Feats of the Millisecond as the micdropping factory, that's why we are snobs against temporal-dismissers luddites around here, especially since nanoseconds can cascade to microseconds can cascade to milliseconds, in things like mutex/semaphore thread-thrash situations in a buggy unfixed Ring 0 device driver that can jitter other things elsewhere in the system....
Yes yes, 128 tick servers give granularity that obscure milliseconds, but even a random 1ms earlier = still 1/8 chance of making an earlier 1/128sec tick and getting that frag. It all builds up over time!
Sure sure, could be 90%-99% placebo, but it's not always, and we don't dismiss if it's more than a 0% chance. We're Blur Busters, the Temporal Mythbusters. Hz, GtG, MPRT, lag, etc.
Sure sure, network issues (and lag compensation etc) dominate the performance issues, but a lot of people do play LAN games, or play against other players on FTTH-only servers (matchmaking that filtered to lowest lag players) in certain game engines that are very precise, or other situations where the millisecond may be more amplified.
Either way:
We're in
over 25 peer reviewed research papers now, and think outside the box on unexpected situations where tiny temporals start to have human visible effects in some use cases.
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