[netperf-talk] Question about burst mode and interval

[George Valzcig]

Hello all,
I have come questions about the burst mode. I have gone through the code and
this is what I have understood from the code so far. Kindly point me out if
I have got anything wrong.

I am working with an example of -t UDP_STREAM -b 5000 -l 10s -w 1s

1) By default the start_timer()sets the SIGALRM catcher and the value of the
ITIMER_REAL to test_len and initializes the test_len_ticks to 1. Then
INTERVALS_INIT() will reset the value of the ITIMER_REAL to 1 second
(specified by -w) and test_len_ticks to 10 (10s / 1s) - correct?.

2) From here on, the timer will pop up and invoke catcher() every one
second. At the end of 10 seconds (when test_len_ticks has decremented to 0),
this will stop the timer and complete the test - correct?

3) At the end of every 5000 (-b) packets being sent, the INTERVALS_WAIT() is
called and the process is SIG_BLOCK'ed. I dont understand how this is
unblocked and next burst sent?

4) Also, lets say that this 5000 packets is sent in 1.5 seconds and then the
SIG_BLOCK happens - how does ensure that the process waits for 1 seconds and
not 0.5 seconds (i.e. till the timer pops up again)?

Thanks
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.netperf.org/pipermail/netperf-talk/attachments/20091006/99513c77/attachment.htm