Quote from: kano on November 11, 2019, 11:54:13 PM

So ... I had a discussion with gmaxwell about ... a while ago ... and he said that the large pools don't purposely make empty blocks any more since it's no longer necessary due to bitcoind being fast enough to not need to do it

(though my pool has proven it was never necessary anyway by never having empty blocks, due to never ignoring all transactions if any are available)

Anyway, today slush produced an empty block 603351

They also found the block before it, 603350.

Now when they found block 603350 and 603351, my bitcoind debug.log shows:

Code:

CreateNewBlock(): block weight: 3965699 txs: 2506 of 8755 fees: 0.43025836 sigops 17480

UpdateTip: new best=0000000000000000000668604f0acc91d12483ea4837f742dffb910d8c7fd84c height=603350 version=0x20002000 log2_work=91.322655 tx=473721413 date='2019-11-11 20:31:12' progress=1.000000 cache=79.0MiB(579629txo) warning='55 of last 100 blocks have unexpected version'

CreateNewBlock(): block weight: 3965648 txs: 2468 of 6252 fees: 0.20234402 sigops 18841

UpdateTip: new best=000000000000000000136973e9bfdfc7151d9929d33fa95827a4107ec5115eed height=603351 version=0x20400000 log2_work=91.322681 tx=473721414 date='2019-11-11 20:31:41' progress=1.000000 cache=79.0MiB(579654txo) warning='56 of last 100 blocks have unexpected version'

CreateNewBlock(): block weight: 3965469 txs: 2463 of 6290 fees: 0.20634536 sigops 18749

i.e. there were at least 8755 transactions available before they found block 603350, of which they used about 2500, and over 6200 transactions available for block 603351 after processing block 603350.

i.e. they purposefully created an empty block 603351 value 12.5 BTC instead of it being at least 12.70234402 BTC and using over 2400 transactions.

So I beg to differ with gmaxwell about his claim that slush pool doesn't code to find empty blocks during a block change

Or, they are running hardware that is stressed to the max and cannot keep up. Or they have something very poorly configured.

I believe in the concept of never believe people are doing something wrong deliberately. It's usually just incompetence. (Look at the Trezor vulnerabilities)

They might not want to generate empty blocks, they might not even be trying to. They just are.

-Dave