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Date: Thu, 23 Jul 2015 16:19:59 +0200
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Subject: [bitcoin-dev] Bitcoin Node Speed Test
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On this day, the Bitcoin network was crawled and reachable nodes surveyed t=
o find their maximum throughput in order to determine if it can safely supp=
ort a faster block rate=2E Specifically this is an attempt to prove or disp=
rove the common statement that 1MB blocks were only suitable slower interne=
t connections in 2009 when Bitcoin launched, and that connection speeds hav=
e improved to the point of obviously supporting larger blocks=2E


The testing methodology is as follows:

=C2=A0* Nodes were randomly selected from a peers=2Edat, 5% of the reachab=
le nodes in the network were contacted=2E

=C2=A0* A random selection of blocks was downloaded from each peer=2E

=C2=A0* There is some bias towards higher connection speeds, very slow con=
nections (<30KB/s) timed out in order to run the test at a reasonable rate=
=2E

=C2=A0* The connecting node was in Amsterdam with a 1GB NIC=2E=20

=C2=A0
Results:

 * 37% of connected nodes failed to upload blocks faster than 1MB/s=2E

 * 16% of connected nodes uploaded blocks faster than 10MB/s=2E

 * Raw data, one line per connected node, kilobytes per second http://past=
ebin=2Ecom/raw=2Ephp?i=3D6b4NuiVQ


This does not support the theory that the network has the available bandwi=
dth for increased block sizes, as in its current state 37% of nodes would f=
ail to upload a 20MB block to a single peer in under 20 seconds (referencin=
g a number quoted by Gavin)=2E If the bar for suitability is placed at taki=
ng only 1% of the block time (6 seconds) to upload one block to one peer, t=
hen 69% of the network fails for 20MB blocks=2E For comparison, only 10% fa=
il this metric for 1MB blocks=2E