C API
#inclucde <os/signpost.h>
os_log_create(), os_log_t
os_signpost_interval_begin
os_signpost_interval_end
os_signpost_event_emit
os_signpost_id_t
Instruments signpost instrument recording opitons > record mode: last 5 seconds (reduces load of signpost in app)
points of interest can mark very important events. they show up in time profiles as well
Custom Instrument custom graphs created in XML ~ 100 lines