Hi, I'm recently developing a rendering engine for WebGL, but met a serious performance issue caused by Scavenge allocation failure issue.
I have a test case which add more and more sprites on the screen, when it's arriving at about 7000 (and stop adding more), the cost of engine is about 6ms per frame, but it grows to 20 ms in seconds. When I add --trace_gc to Chrome, I see the behavior is totally related to a huge amount of Scavenge allocation failure log, like the following [33525:0x7fa78280fc00] 955497 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 955580 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 955663 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 955747 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 955830 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 955913 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 955998 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956084 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956170 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956254 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956335 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956418 ms: Scavenge 37.0 (46.5) -> 35.1 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956502 ms: Scavenge 37.0 (46.5) -> 35.2 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956584 ms: Scavenge 37.0 (46.5) -> 35.2 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956667 ms: Scavenge 37.0 (46.5) -> 35.2 (46.5) MB, 0.3 / 0.0 ms allocation failure [33525:0x7fa78280fc00] 956752 ms: Scavenge 37.0 (46.5) -> 35.2 (46.5) MB, 0.3 / 0.0 ms allocation failure ... (it keeps printing very fast) However, when I do a allocation profiling, it shows that the JS heap size is quite low (36mb), and I generate nearly nothing in heap <https://lh3.googleusercontent.com/--jVjhgqdtrY/WiZyTYxyk8I/AAAAAAAAAHg/1XpXYumxrnMQ-oPirMT-JLm-dM6af5DdACLcBGAs/s1600/Screen%2BShot%2B2017-12-05%2Bat%2B6.15.56%2BPM.png> Some additional information, we tried very hard to reduce memory allocation in the engine core, so we used a lot of object pools and pre-generated objects, including some large array buffers, largest one is 20000 * 6 floats, and we keep recycling / updating these objects. I also tried to check jit status, no hot functions is being deoptimized, the scavenge log is the only thing related to the strange performance drop down. Does anyone have a clue on my problem ? Thanks a lot for helping Huabin -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
