Over the past few days, there have been multiple discussions regarding the Bitcoin mempool. It is true the number of transactions is on the rise again. Moreover, confirmation times for transactions are growing much longer than some people are comfortable with.
The Current Bitcoin Mempool State
It does not take much effort to see why some people are getting riled up this week. There is a clear increase in the Bitcoin mempool size and transaction confirmation delays. Several factors can contribute to this development, although pinpointing the exact reason will always be difficult. Ever since October 25th came to pass, there has been a 720% increase in unconfirmed Bitcoin transactions.
At the same time, there is a clear increase in pending transaction fees. The vast majority of BTC transfers is still in the “acceptable fee” range, though, Anything under 150 Satoshi per byte is not too dramatic, all things considered. What is remarkable, however, is the triple peak in high-fee transactions. More often than not, including a higher fee gets transactions confirmed faster. That is, given these circumstances, not always guaranteed.
Looking at the Bitcoin mempool in terms of actual size, things are getting interesting. There has been a clear increase in size since October 25th. Something clearly happened on that day, and it is still creating shockwaves today. As the mempool size increases, there is often some concern.
Currently, the biggest size in the past week has been just over 87 MB. That is more than sufficient to ensure all pending transactions will be processed sooner or later. Bitcoin network nodes can keep a backlog of up to 300 MB. As such, there is no concern on that front. That said, the current situation is far from ideal, for obvious reasons.
Non-SegWit Transaction Remain Dominant
When looking at the nature of the Bitcoin mempool transactions, interesting statistics can be obtained. The chart below clearly confirms there are still a lot of non-SegWit transactions. While the use of SegWit may not necessarily avoid mempool congestion altogether, it is a bit worrisome to see this low rate of adoption today.
The introduction of SegWit occurred quite a while back. Many people hoped to see the entire network benefit from this solution by now. Clearly, that is not the case. A bit odd, considering how SegWit is designed to be a capacity increase. Network blocks can fit more transactions in the same size. Broader adoption can help alleviate some mempool concerns further down the line.
Over the past few days, the amount of SegWit transactions is outdone by non-SegWit transfers. This further confirms the adoption of Segregated Witness remains a key issue. Addressing that situation won’t be straightforward. Service providers of all sizes will need to step up their game in this particular regard.