Overflow count in Storm logs

[Muhammad Bilal]

Hi,

I am collecting some logs from my Storm topology using
LoggingMetricConsumer. However, I am seeing an interesting behaviour. The
send queue stats from one of the bolts is as follows:

"__sendqueue             {sojourn_time_ms=0.4088741    648526843,
write_pos=6333002, read_pos=6332949, arrival_rate_secs=129624.23296931878,
overflow=39, capacity=8192, population=53}"

My question is: why is there non-zero overflow when the population is just
53?

I am using Storm 1.0.1.

Thanks.

-Bilal