wiki:latency_mon

Version 5 (modified by branden, 8 years ago) (diff)

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Earthworm Module: latency_mon

Contributed by: Paul Whitmore at West Coast Alaska Tsunami Warning Center and John Patton, USGS

Function

track data outages and latencies for all channels

Logs and displays latency and outages of data from a specified ring (Windows only)

Details

This program takes waveforms dropped in InRing and logs latency and outages of the data. Each time a trace arrives, its start time is compared to the end time of the last packet. When there is a gap the outage is logged to a data file for that station. Also, the start time is compared to real-time, and latency is determined. Whenever the latency changes, it is also logged with start and end time to the file. Latencies are grouped generally: <1' = 0; 1'-2' = 1; 2'-3' = 2; 3'-5' = 3; >5' = 4. Here, latency is described as present time minus mid-time of the packet.

The graphical output shows a line for each station in the .sta file for a set length of time. Colors on the line represent the latency of the station over that time interval.

This will only give accurate outage values if this module is running all the time the earthworm system is up.

This module is strictly for use under Windows.

Written by Paul Whitmore, (WC/ATWC) August, 2001 Modified by John Patton (USGS) July, 2002

  Usage:  get_latency <name of configuration file>    

See also: http://wcatwc.arh.noaa.gov/DataProcessing/latency_mon.htm

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