Site Bandwidth Testing

The above is a bandwidth test done using the tool iperf (version iperf_2.0.2-4_i386) between the site KISTI (ui03.sdfarm.kr) and BNL (stargrid03) around the beginning of the year 2014. The connection was noted to collapse (drop to zero) a few times during testing before a full plot could be prepared.

The above histogram shows the number of simultaneous copies in one minute bins, extracted from a few week segment of the actual production at KISTI. Solitary copies are suppressed because they overwhelm the plot. Copies represent less than 1% of the jobs total run time.

The above is a bandwidth test done using the tool iperf (version iperf_2.0.2-4_i386) between the site Dubna (lxpub01.jinr.ru) and BNL (stargrid01) on 8/14/2015. After exactly 97 parallel connections the connection was noted to collapse with many parallel processes timing out, this behavior was consistent across three attempts but was not present at any lower number of parallel connections. It is suspected that a soft limit is placed on the number of parallel processes somewhere.The raw data is attached at the bottom.