duplicate 'Got Block' notices on pre-hf and hf version 2.0.171105a

This might not be a big issue and might just be a glitch however both nahu and myself noticed today 8 december that on our nodes (both pre-hf and new hf 2.0.171105a nodes) the stdout showed some duplicate 'Got Block' entries with just a minor latency difference like these:

Bhuz suggested it might have to do with ram. Upon inspecting free -m this is the ram output:
 So mainly a lot in 'buffers/cache' .

Bhuz suggested the following:
`echo 3 > /proc/sys/vm/drop_caches` [learn more here](https://unix.stackexchange.com/questions/17936/setting-proc-sys-vm-drop-caches-to-clear-cache)

Not sure if it is coincidental, but after that I don't see anymore of these duplicate 'Got Block' entries.
@abitmore asked me to file this notice, for future research, so there you go!

Start by reproducing the duplicate “Got Block” stdout entries on both pre-hf and hf 2.0.171105a nodes, while recording the memory state shown by free -m. Compare behavior before and after clearing caches with the reported command; done when the cause of the duplicate notices is identified and the result is documented.

Written by the indexing model from the issue text.