+For both the option:--timer and option:--size options, LTTng checks the
+schedule condition periodically using the monitor timers of the channels
+of the selected tracing session (see the nloption:--monitor-timer option
+of man:lttng-enable-channel(1)). This means that:
+
+* With the option:--timer='PERIODUS' option, LTTng can perform an
+ automatic rotation when the elapsed time since the last automatic
+ rotation is slightly greater than 'PERIODUS'.
++
+The exact precision depends on the precision of the monitor timer, which
+relies on the precision of the platform implementation of POSIX timers.
+
+* With the option:--size='SIZE' option, LTTng can perform an automatic
+ rotation when the size of the flushed part of the current trace chunk
+ is greater than 'SIZE'.
+
+You may combine the option:--timer and option:--size options.