Binaries or shared libraries/objects that contain debug symbols have their symbols extracted and uploaded to the remote server. The remote server can then use it to symbolize the stack traces at read time rather than in the agent.

https://www.parca.dev/docs/parca-agent-design/ そうっぽい

Parca Agent implements a sampling profiler, to sample stack traces 19 times per second per logical CPU via eBPF. It tracks user space as well as kernel-space stack traces. From the raw data, it builds a pprof formatted profile and optionally sends it to a Parca server where it is stored and can be queried and analyzed over time.