I want to calculate net transfer of bytes(in & out) for every 2 seconds.
nettop to know the usage(
nettop -x -k state -k interface -k rx_dupe -k rx_ooo -k re-tx -k rtt_avg -k rcvsize -k tx_win -k tc_class -k tc_mgt -k cc_algo -k P -k C -k R -k W -l 1 -t wifi -t wired
bytes_out according to application summary.
1Q). The data(
bytes_out) displayed is calculated from startup for every application. Am I right?
I thought I'm right and ran the
nettop command two times with 2 seconds interval and subtracted these two values to get the net transfer of bytes for 2 seconds.
But sometimes, the first output is greater than second output.
2Q). How is that possible? Always the second output must be greater or equal to first output right?
OS: macOS Sierra.