Performance counters stops before expected time

Hi Gurus

I'm confused and wondering why my performance counters stop automatically before the set time?
I have create task under perfmon and put in stop condition for 6 hours but every time logs in the file shows trace result for 1 hour or so.
can someone please help me in figuring out this issue, Is i'm doing something wrong while scheduling counters ?

fyi ... I'm starting trace manually from performance monitor

Thanks in advance

Is there a maximum file size that it's hitting at 1 hour?

Sorry for the late reply, Max file setting was not on.
i think there might be some configuration setting left unattended because there is no such logs or something that point out to issue.