(autoload 'profiler-start "profiler" "\
Start/restart profilers.
MODE can be one of `cpu', `mem', or `cpu+mem'.
-If MODE is `cpu' or `cpu+mem', time-based profiler will be started.
-Also, if MODE is `mem' or `cpu+mem', then memory profiler will be started.
+If MODE is `cpu' or `cpu+mem', start the time-based profiler,
+ whereby CPU is sampled periodically using the SIGPROF signal.
+If MODE is `mem' or `cpu+mem', start profiler that samples CPU
+ whenever memory-allocation functions are called -- this is useful
+ if SIGPROF is not supported, or is unreliable, or is not sampling
+ at a high enough frequency.
\(fn MODE)" t nil)