Subject: Re: [bitcoin-dev] Bitcoin Node Speed Test

From: Peter Todd <[email-masked]>
Date: Thu, 23 Jul 2015 16:05:11 +0000

On 23 July 2015 10:19:59 GMT-04:00, slurms--- via bitcoin-dev <[email-masked]> wrote:
>This does not support the theory that the network has the available
>bandwidth for increased block sizes, as in its current state 37% of
>nodes would fail to upload a 20MB block to a single peer in under 20
>seconds (referencing a number quoted by Gavin). If the bar for
>suitability is placed at taking only 1% of the block time (6 seconds)
>to upload one block to one peer, then 69% of the network fails for 20MB
>blocks. For comparison, only 10% fail this metric for 1MB blocks.

Note how due to bandwidth being generally asymetric your findings are probably optimistic - you've measured download capacity. On top of that upload is further reduced by the fact that multiple peers at once need to be sent blocks for reliability.

Secondly you're measuring a network that isn't under attack - we need significant additional margin to resist attack as performance is consensus-critical.