VDiff too high for low-hashrate miners; settings ignored

[marcusmayo]

Summary:
Running Datum Gateway on Start9 with low-hashrate miners (Bitaxe Gamma @1.2 TH/s, Avalon Nano3s @6 TH/s).
Despite setting vardiff_min: 8, difficulty: 64, and even vardiff_enable: false, clients still receive VDiffs of 4096 and 32768.

What I expected:

• Honor the low vardiff_min value.
• Respect fixed difficulty: when VarDiff is disabled.
• Allow small miners to operate with practical fixed difficulty.

Configuration excerpt:

stratum:
  vardiff_enable: false
  vardiff_min: 8
  difficulty: 64
fingerprint_miners: false


Result observed:
Bitaxe shows VDiff = 4096
Nano3s shows VDiff = 32768

Environment:
Datum Gateway v0.3.1
Start9 OS
Client devices: Bitaxe Gamma, Avalon Nano3s

Steps to reproduce:
Install Datum Gateway on Start9
Connect a low-power miner
Configure low vardiff_min or disable VarDiff
Observe VDiff values in the gateway UI

Request:
Please adjust config logic so that low vardiff_min and difficulty are honored, enabling small solo miners.

[wizkid057]

Few things:

• Vardiff minimum only applies when lotto solo mining if it's below the pool's minimum vardiff
• There is no vardiff enable config...?
• The server will adjust vardiff to target the number of shares per minute designated, default of 8

More importantly, vardiff doesnt actually impact anything whatsoever when lotto mining anyway.