# GPU Debugger and Profiler reporting different Render Command execution times - how to find the gap? **URL:** \ **Category:** Metal by Tutorials\ **Created:** [April 25, 2021, 11:05pm UTC](https://forums.kodeco.com/t/gpu-debugger-and-profiler-reporting-different-render-command-execution-times-how-to-find-the-gap/138597 "2021-04-25T23:05:31Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![flash3001](https://assets.chunter.kodeco.com/user_avatar/forums.kodeco.com/flash3001/32/81494_2.png) [@flash3001](https://forums.kodeco.com/u/flash3001)\ **Post date:** [April 25, 2021, 11:05pm UTC](https://forums.kodeco.com/t/gpu-debugger-and-profiler-reporting-different-render-command-execution-times-how-to-find-the-gap/138597/1 "2021-04-25T23:05:31Z")
Hello, I am using ICBs to render a scene and at some points I am having some frame drops, but the data provided by the GPU Debugger seems off when compared to the Profiler when those drops occur. When the render is running smooth both tools give a timing that is “close enough” for the Render Command when I call executeCommandsInBuffer: 7.85ms (GPU Debugger) and 9.90 ms (Profiler). I say close enough because the scene is dynamic generated, but I tried to measure based on points that looked very close. But when I am seeing the part of the scene that causes the drops the reports are 9.38ms (GPU Debugger) and 18.52ms (Profiler) - for the Render Command only. So far I was not able to figure out why they report different timings, what the Profiler reports matches the frame drops. Is there any other tool or window I can look to figure out what is going on? In the profiler it reports the ~18ms but that is all. Here is a screenshot of both tools when it is running at 60fps with timing reports close enough: ![Screen Shot 2021-04-25 at 19.33.56](https://files.chunter.kodeco.com/original/3X/0/e/0ebca09ad87d37b9cc908abcc10263a6d5a06978.jpeg) ![Screen Shot 2021-04-25 at 19.37.38](https://files.chunter.kodeco.com/original/3X/3/0/30d9bbca84f59f3a488f4a18c2d86f16d44bd7ca.png) And for the the part of the view with drops: ![Screen Shot 2021-04-25 at 19.39.32](https://files.chunter.kodeco.com/original/3X/c/9/c9f670f048eff3bb2b8da5ba3836525c350f28cd.png) ![Screen Shot 2021-04-25 at 19.43.34](https://files.chunter.kodeco.com/original/3X/3/a/3a1530f77b7a6b8fe4e30f51324332a298864f12.png) ---
**Author:** ![caroline](https://assets.chunter.kodeco.com/user_avatar/forums.kodeco.com/caroline/32/111867_2.png) [@caroline](https://forums.kodeco.com/u/caroline)\ **Post date:** [April 25, 2021, 11:46pm UTC](https://forums.kodeco.com/t/gpu-debugger-and-profiler-reporting-different-render-command-execution-times-how-to-find-the-gap/138597/2 "2021-04-25T23:46:05Z")
I can’t suggest anything I’m afraid. Instruments (Profiler) would be the most accurate. Maybe there’s something in the WWDC videos: > **[Gain insights into your Metal app with Xcode 12 - WWDC20 - Videos - Apple...](https://developer.apple.com/videos/play/wwdc2020/10605/)** > > Learn how to locate graphics issues in minutes with Metal's debugging and performance optimization tools in Xcode 12. We'll show you how... > **[Delivering Optimized Metal Apps and Games - WWDC19 - Videos - Apple Developer](https://developer.apple.com/videos/play/wwdc2019/606/)** > > Optimizing performance, memory, and bandwidth are important considerations for resource-intensive Metal apps and games. Learn key best... > **[Optimize Metal apps and games with GPU counters - WWDC20 - Videos - Apple...](https://developer.apple.com/videos/play/wwdc2020/10603/)** > > GPU counters can help you precisely measure GPU utilization to pinpoint bottlenecks and optimize workloads for your Metal apps and games... > **[Metal Shader Debugging and Profiling - WWDC18 - Videos - Apple Developer](https://developer.apple.com/videos/play/wwdc2018/608/)** > > Metal provides powerful tools for analyzing shader behavior and optimizing performance. Dive into troubleshooting vertex-stage problems...