2 months ago
- Measure performance impact of eBPF code using a simple C test harness that times file open operations via syscall(SYS_openat) under warm cache conditions.
- Enable BPF JIT and expose symbols via sysctl commands so perf can resolve eBPF program names instead of unknown addresses.
- Run baseline test without eBPF, then profile with eBPF using perf record with options like taskset, chrt, frame pointers, and 997 samples per second.
- Analyze perf report to identify bottlenecks, such as the bpf_lsm_file_open hook and its tail calls, which can dominate overhead.
- Focus on the profiling method; actual overhead depends on the eBPF hook's implementation and can be optimized via caching or better algorithms.