Miguel Raz Guzmán Macedo
and
Joseph T. Lyons
created
Self-Review Checklist:
- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable
Closes #ISSUE
Release Notes:
- N/A or Added/Fixed/Improved ...
Co-authored-by: Joseph T. Lyons <JosephTLyons@gmail.com>
@@ -15,7 +15,7 @@ See [samply](https://github.com/mstange/samply)'s README on how to install and r
The profile.json does not contain any symbols. Firefox profiler can add the local symbols to the profile for for. To do that hit the upload local profile button in the top right corner.
-<img width="851" height="auto" alt="image" src="https://github.com/user-attachments/assets/cbef2b51-0442-4ee9-bc5c-95f6ccf9be2c" />
+<img width="851" height="auto" alt="image" src="https://github.com/user-attachments/assets/cbef2b51-0442-4ee9-bc5c-95f6ccf9be2c" style="display: block; margin: 0 auto;" />
# In depth CPU profiling (Tracing)
@@ -53,20 +53,40 @@ Download the profiler:
Open the profiler (tracy-profiler), you should see zed in the list of `Discovered clients` click it.
-<img width="392" height="auto" alt="image" src="https://github.com/user-attachments/assets/b6f06fc3-6b25-41c7-ade9-558cc93d6033" />
+<img width="392" height="auto" alt="image" src="https://github.com/user-attachments/assets/b6f06fc3-6b25-41c7-ade9-558cc93d6033" style="display: block; margin: 0 auto;"/>
Tracy is an incredibly powerful profiler which can do a lot however it's UI is not that friendly. This is not the place for an in depth guide to Tracy, I do however want to highlight one particular workflow that is helpful when figuring out why a piece of code is _sometimes_ slow.
Here are the steps:
1. Click the flamechart button at the top.
+
+<img width="1815" height="auto" alt="Click flamechart" src="https://github.com/user-attachments/assets/9b488c60-90fa-4013-a663-f4e35ea753d2" />
+
2. Click on a function that takes a lot of time.
+
+<img width="2001" height="auto" alt="Click snapshot" src="https://github.com/user-attachments/assets/ddb838ed-2c83-4dba-a750-b8a2d4ac6202" />
+
3. Expand the list of function calls by clicking on main thread.
+
+<img width="2313" height="auto" alt="Click main thread" src="https://github.com/user-attachments/assets/465dd883-9d3c-4384-a396-fce68b872d1a" />
+
4. Filter that list to the slower calls then click on one of the slow calls in the list
+
+<img width="2264" height="auto" alt="Select the tail calls in the histogram to filter down the list of calls then click on one call" src="https://github.com/user-attachments/assets/a8fddc7c-f40a-4f11-a648-ca7cc193ff6f" />
+
5. Click zoom to zone to go to that specific function call in the timeline
+
+<img width="1822" height="auto" alt="Click zoom to zone" src="https://github.com/user-attachments/assets/3391664d-7297-41d4-be17-ac9b2e2c85d1" />
+
6. Scroll to zoom in and see more detail about the callers
+
+<img width="1964" height="auto" alt="Scroll to zoom in" src="https://github.com/user-attachments/assets/625c2bf4-a68d-40c4-becb-ade16bc9a8bc" />
+
7. Click on a caller to to get statistics on _it_.
+<img width="1888" height="auto" alt="Click on any of the zones to get statistics" src="https://github.com/user-attachments/assets/7e578825-2b63-4b7f-88f7-0cb16b8a3387" />
+
While normally the blue bars in the Tracy timeline correspond to function calls they can time any part of a codebase. In the example below we have added an extra span "for block in edits" and added metadata to it: the block_height. You can do that like this:
```rust
@@ -74,14 +94,6 @@ let span = ztracing::debug_span!("for block in edits", block_height = block.heig
let _enter = span.enter(); // span guard, when this is dropped the span ends (and its duration is recorded)
```
-<img width="1815" height="auto" alt="Click flamechart" src="https://github.com/user-attachments/assets/9b488c60-90fa-4013-a663-f4e35ea753d2" />-<img width="2001" height="auto" alt="Click snapshot" src="https://github.com/user-attachments/assets/ddb838ed-2c83-4dba-a750-b8a2d4ac6202" />-<img width="2313" height="auto" alt="Click main thread" src="https://github.com/user-attachments/assets/465dd883-9d3c-4384-a396-fce68b872d1a" />-<img width="2264" height="auto" alt="Select the tail calls in the histogram to filter down the list of calls then click on one call" src="https://github.com/user-attachments/assets/a8fddc7c-f40a-4f11-a648-ca7cc193ff6f" />-<img width="1822" height="auto" alt="Click zoom to zone" src="https://github.com/user-attachments/assets/3391664d-7297-41d4-be17-ac9b2e2c85d1" />-<img width="1964" height="auto" alt="Scroll to zoom in" src="https://github.com/user-attachments/assets/625c2bf4-a68d-40c4-becb-ade16bc9a8bc" />-<img width="1888" height="auto" alt="Click on any of the zones to get statistics" src="https://github.com/user-attachments/assets/7e578825-2b63-4b7f-88f7-0cb16b8a3387" />-
# Task/Async profiling
Get a profile of the zed foreground executor and background executors. Check if