We just shipped a huge update to the Timeline Profiler in Tideways that improves the level of detail and usability of this core profiling feature. This is the first major step of several more updates to come in the next month.
First, we have added a clear parent-child relationship between timespans in the timeline, so that a child span is now rendered below its parent in almost all cases.
In addition we now show the list of parents of a selected span in the details panel:
That is not the only information that we have added, with the release of PHP extension version 4.1.3 and daemon 1.5.8 we are now collecting the last 10 stack-trace frames of a span that takes longer than 50 milliseconds.
You can configure this threshold to be lower if your application is very fast but we recommend it not be lower than 5-10% of your usual response time. We are still experimenting a little with the exact limits, but daemon and backend post-filter the amount of stacktraces depending on your plan.
The third improvement we shipped is a zoom behaviour for the timeline itself. When your trace has many small SQL or HTTP queries, potentially on various different datasources, then it helps to select just a portion of the timeline and look at the exact timings of each span more closely.
Using zoom is intuitive and uses a drag and drop behaviour to select the timeline.