Broadband Speeds, New Data

Thanks to edmundedgar on reddit I have some more accurate data to update my previous bandwidth growth estimation post: OFCOM UK, who released their November 2014 report on average broadband speeds.  Whereas Akamai numbers could be lowered by the increase in mobile connections, this directly measures actual broadband speeds. Extracting the figures gives: Average download […]

The Megatransaction: Why Does It Take 25 Seconds?

Last night f2pool mined a 1MB block containing a single 1MB transaction.  This scooped up some of the spam which has been going to various weakly-passworded “brainwallets”, gaining them 0.5569 bitcoins (on top of the normal 25 BTC subsidy).  You can see the megatransaction on It was widely reported to take about 25 seconds […]

Mining on a Home DSL connection: latency for 1MB and 8MB blocks

I like data.  So when Patrick Strateman handed me a hacky patch for a new testnet with a 100MB block limit, I went to get some.  I added 7 digital ocean nodes, another hacky patch to prevent sendrawtransaction from broadcasting, and a quick utility to create massive chains of transactions/ My home DSL connection is […]

What Transactions Get Crowded Out If Blocks Fill?

What happens if bitcoin blocks fill?  Miners choose transactions with the highest fees, so low fee transactions get left behind.  Let’s look at what makes up blocks today, to try to figure out which transactions will get “crowded out” at various thresholds. Some assumptions need to be made here: we can’t automatically tell the difference […]

Current Blocksize, by graphs.

I used bitcoin-iterate and gnumeric to render the current bitcoin blocksizes, and here are the results. My First Graph: A Moment of Panic This is block sizes up to yesterday; I’ve asked gnumeric to derive an exponential trend line from the data (in black; the red one is linear) That trend line hits 1000000 at […]