if you use collectd to feed values into graphite, you've got the advantage of its bulk writes. This article describes how its solved for rrd only collectd installations: https://collectd.org/wiki/index.php/Inside_the_RRDtool_plugi... but the effect also becomes visible if you use it to send values to graphite.
Its also good in reducing the amount of data you need to send to graphite.
How do you figure? Unless recent versions of Whisper have been totally rewritten, whisper writes each metric to a separate file. Submit hundreds of metric per vm/server every 10 seconds, and you get ridiculous amounts of tiny writes (e.g. 4 byte writes) fenced by redundant seek()'s and a number of other syscalls, no matter how much you batch up stuff before sending it to statsd.
Its also good in reducing the amount of data you need to send to graphite.