Published on: 2015-08-20T14:27:20+00:00
A member of the bitcoin-dev mailing list has expressed concern over miners producing empty blocks despite having fully verified the previous block, leading to suspicion that the mining hardware and software itself may be at fault. Empty blocks have been mined by several different pools despite there being preceding blocks as small as 50KB with 30s passing and the miner continues to mine empty blocks via SPV mining. If miners are SPV mining for a significant portion of the hashing power, all a single malicious miner has to do is mine an invalid block on purpose, let these pools SPV mine on top of them while it mines a valid block free of their competition. The impact of this could be more mining centralization, which is already too centralized today. A post on the bitcoin-dev mailing list indicates that nodes are technically capable of handling blocks larger than the current block size limit. However, data shows that even miners who have all the incentives are struggling to download and validate much smaller blocks. Empty blocks have been mined despite a non-trivial elapsed time from the previous block. This is concerning because if miners continue to SPV mine for a whole minute, a malicious miner could mine an invalid block on purpose and let these pools SPV mine on top of them while it mines a valid block free of their competition. This would lead to reorgs and many block orphans for anyone not running a full node, which could be disastrous in the XT world where Mike wants everyone to be running SPV nodes. The impact of this could be more mining centralization, which is already too centralized today. It is unclear why this is happening, and there are several steps of latency involved in the process.The author of an email to the bitcoin-dev mailing list is concerned about the capacity of miners to handle smaller blocks. The author notes that while half a million dollars in revenue may seem like a lot, it means little if running costs are also high. The author points out that there have been instances where miners have been struggling to download and validate much smaller blocks, leading to empty blocks being mined despite non-trivial elapsed time from the previous block. The author suggests that this could be due to bad mining codes or laziness on the part of miners. The author is particularly worried about the implications of miners resorting to SPV mining, as this could lead to disastrous consequences in the event of a malicious miner mining an invalid block on purpose. If these pools go out of business, it would lead to even more mining centralization which is already too centralized today. The author calls for representatives of these pools to comment on why this is happening and whether they are on Matt's relay network.The bandwidth and validating capacity of the global mining network is causing concern for bitcoin developers. Despite having all the incentives, miners are still struggling to download and validate small blocks. This is proven by empty blocks mined despite a non-trivial elapsed time from the previous block. The most glaring case is Block 370057, where despite 73 seconds elapsing and the preceding block being a mere 131KB, the miner was unable to download/validate fast enough to include transactions in their block. If miners are SPV mining for a whole minute for just fall apart as a significant portion of the hashing power SPV mines throughout. This could lead to disastrous consequences if a single malicious miner mines an invalid block on purpose and lets these pools SPV mine on top of them while it mines a valid block free of their competition. It could impact reorgs and many block orphans for anyone not running a full node, which could be disastrous, especially more so in the XT world where Mike wants everyone to be running SPV nodes.The author has been monitoring the blockchain and noticed that even miners are struggling to download and validate smaller blocks. They believe that nodes are capable of handling blocks much larger than the current block size limit, but there is no incentive to run them. The data shows empty blocks being mined despite a non-trivial elapsed time from the previous block, and some miners are continuing to mine empty blocks via SPV mining even with preceding blocks as small as 50KB. This raises concerns about the global mining network's bandwidth and validating capacity. Unless miners are intentionally mining empty blocks, which does not make sense, this issue needs to be addressed.
Updated on: 2023-08-01T15:26:00.259025+00:00