fix: reset extranonce2 only if clean_jobs == true

[blackmennewstyle]

This PR improves the extranonce2 reset.
It is only performed if clean_jobs == true.
The previous code was triggering a cascade of duplicate shares after a varDiff change:

• mining.set_difficulty
• mining.notify with clean_jobs is set to false The behavior is described here: esp-miner is unable to handle difficulty change following with "mining.notify" when cleanJob set to false #1587 (comment)

[blackmennewstyle]

@mutatrum Hi there, should i close my PR? It is obvious that you guys don't want to fix the issue with the extranonce2 reset according to the proper cleanJob flag.

At least be honest and give a reason for the lack of interest. I'm not the only one affected with that issue, that pool operator is also impacted #1595 (comment) and literally everyone using the stratum software miningcore.

That 8 lines of code does not hurt the other stratum software either in any single way, i tested on CKPOOL and SOLOPOOL.

[blackmennewstyle]

New PR #1694 : Based on your StratumV2 which allegedly was supposed to fix the issue but unfortunately, the root of the problem extranonce2 = 0 which naively resets for every single job without taking in account the cleanJob state, has NOT been tackled within the STRATUM V2 changes.

[mutatrum]

@mutatrum Hi there, should i close my PR? It is obvious that you guys don't want to fix the issue with the extranonce2 reset according to the proper cleanJob flag.

At least be honest and give a reason for the lack of interest. I'm not the only one affected with that issue, that pool operator is also impacted #1595 (comment) and literally everyone using the stratum software miningcore.

That 8 lines of code does not hurt the other stratum software either in any single way, i tested on CKPOOL and SOLOPOOL.

It's more that we haven't seen it on the pools we normally test, and nobody has tried to reproduce it on your pool yet. Lack of time, lack of users reporting the issue and it's unclear if it is the correct way of fixing it, if there is anything to fix. Ckpool also does vardiff and it doesn't happen there.

It's good you reopened it against master with SV2 merged, and now that's out of the way we can have a look at this.