Agent flush intervals converge

[obfuscurity]

I was running a haggar test last night that started fine and ran as expected until I noticed some odd behavior this morning. Typically I'll start some number of agents with the default flush-interval and jitter settings, and see a constant stream of flushes logged to stderr.

$ GOPATH=~/gocode ./gocode/bin/haggar -agents=100 -metrics=4000 -carbon="x.x.x.x:2003"

When I checked on the benchmark today I observed some unusual behavior on the Carbon node; I traced it back to Haggar, where all of the agents where flushing at the same time, every 10 seconds. This is very unusual and certainly not the desired/expected behavior, which is to flush on a interval relative to each agent's (staggered) start time.