Solutions

Find the slow service, then the call that made it slow.

Slow applications come down to three questions: which service, which request, which call. Services, Traces and Topology answer them in that order.

What you get

Services shows each one with its request volume, failed share and p95 latency, worst first.

Traces sorts by slowest, filters by minimum duration, and draws a histogram of how durations are spread.

Open a trace to see the waterfall and highlight its critical path. Topology shows the calls between services and how many failed.

Start at Services
Open the one at the top of the list.
Open its slowest traces
Use the button in the service drawer, then sort by slowest.
Read the waterfall
Find the span that takes the time, and open the logs for it.
Keep watching
Create a latency SLO or an alert rule so the next regression finds you.