PerfDog User’s Guide（2）

Software Performance Information Collection:
iOS platform (aligned with the parameters of Apple’s official Xcode tool. Note: The iOS system has strict limits on process performance parameters. If the limit is exceeded, the system will be killed.)
l ScreenShot (only supports USB mode)
l FPS (The average number of refresh of game interface or application interface in 1 second, commonly known as Frames Per Second/FPS)

1. Avg (FPS): The average number of FPS (FPS average over a period of time)
2. Var (FPS): FPS variance (FPS variance over a period of time)
3. Drop (FPS):The number of frame drop(The average number of adjacent two FPS points drop more than 8 frames per hour)
   l Jank (The number of lag in 1 second, iOS9.1 and below systems are temporarily not supported. Similar to Android’s Jank and iOS’s FramePacing smoothness statistics principle. FPS is high doesn’t mean smooth. For example: The FPS is 50, rendering 1 frame in the first 200ms, rendering 49 frames in the remaining 800ms, although the FPS is 50, it doesn’t feel smooth. At the same time, FPS is low, which does not represent a lag. For example, if there is no lag, the average FPS is 15 frames. Therefore, the average FPS has no direct relationship with lag.)
   Reference：https://bbs.perfdog.qq.com/article-detail.html?id=38
   PerfDog calculation method:

At the same time satisfying two conditions, it is considered to be a Jank.
a) Current frame time consumption > Twice the average time of the previous three frames.
b) Current frame time > Two frames of movie frame time (1000ms/242=84ms).
At the same time, satisfying two conditions is considered to be a serious BigJank.
a) Current frame time consumption > Twice the average time of the previous three frames.
b) Current frame time > Three frames of movie frame time (1000ms/243=125ms).

1. BigJank: The number of serious lag in 1 second
2. Jank (/10min): The average number of Jank per 10 minutes
3. BigJank (/10min): The average number of BigJank per 10 minutes

l Stutter (The percentage of the stutter time during the test)

l FTime ( Up and down frame display time interval, that is frame time-consuming, iOS9.1 and below systems are temporarily not supported.)