Computing Division reaches data traffic milestone
Last month, Fermilab set a record for inbound, archived and outbound traffic, which is shown in the graph.
Last month, while many of the laboratory's departments were preparing for shutdown, Fermilab's network moved record volumes of both incoming and outgoing data. In July, total archived data reached a record of 6 petabytes, while data sent from the lab exceeded 2 petabytes, more than double the amount leaving the lab three months ago.
"Our traffic has been growing in terms of the amount of bytes we move onto the site as the LHC and CMS experiments ramp up," said Matt Crawford, the department head for Data Movement and Storage in Fermilab's Computing Division.
In June, outgoing data reached one-and-a-half petabytes, but prior to a year ago, traffic never exceeded a fourth of a petabyte in a month, Crawford said. He attributes the increase in both outgoing and incoming data to CMS, DZero and CDF collaborators actively moving data for analysis.
"Fermilab is one of seven Tier 1 sites for the CMS experiment, and over the last 120 days, Fermilab has supplied three fourths of the data that has been sent to the Tier 2 sites," Crawford said.
Fermilab also reached a record six petabytes (six million gigabytes) of data permanently recorded on tape. Crawford explained that disc storage is not reliable or economical over long times, so data is recorded to tapes, which can then be accessed later when data is needed.
Although the amount of incoming and outgoing data is growing quickly, Crawford said that the Computing Division has managed to stay "abreast or ahead" when it comes to infrastructure capacity. Currently the external network capacity is 60 gigabits per second, while an average desktop computer's connection is one-tenth of a gigabit per second.
If upgrades are necessary, the infrastructure is already in place. "We can add capacity at a low marginal cost," he said. "We would just send more different colors of light, different wavelengths, through our metropolitan optical fiber network to the Department of Energy's network interchanges in Chicago."