Vardiff and static share difficulty
How vardiff tunes your share difficulty, why it never changes your earnings, when to pin a static value, and the share difficulty on each HeroMiners pool.
What does vardiff do?
Share difficulty decides how hard a single share is to find. Variable difficulty, or vardiff, times how fast your rig submits shares. It then retunes the difficulty until shares arrive at a steady target pace.
A big rig gets harder shares and a small rig easier ones. Nothing has to be set by hand. When your hashrate changes, the difficulty follows it: a card throttles, a rig is retuned or a GPU drops out.
Does share difficulty change what you earn?
No. A harder share is rarer and counts for proportionally more. So the same rig credits the same work in the same time at any difficulty.
Raising the difficulty does not earn more, and lowering it does not either. Only the rhythm of submission changes.
Solo mining is no different. A block is found when one hash beats the network difficulty. Your chance depends only on your hashrate against the network's, never on how often the pool hears from your rig.
Why does a steady share pace matter?
A difficulty that is too easy floods the pool and your connection with tiny shares. One that is too hard makes shares so rare that your dashboard hashrate swings wildly. A restart then also wastes more work that was in flight.
The target pace is the balance point. For almost everyone, vardiff finds it better than a hand-picked number.
When does a static difficulty help?
Most HeroMiners pools let you pin a fixed difficulty (see the list of pools below). It helps in a few real cases:
- Proxy setups that combine many small workers.
- Hashrate rented from a marketplace that behaves badly during retarget steps.
- Benchmarking, where you want share counts you can compare across runs.
If none of those is you, leave vardiff on.
When does a static difficulty hurt?
A fixed difficulty far below your rig's natural level wastes bandwidth and pool capacity, for zero extra earnings. One far above it makes your stats noisy and slow to settle.
If you do pin a value, start from the difficulty vardiff settled on rather than a guess. Your miner's console shows it.
How do you set a static difficulty?
Add an equals sign and the difficulty to the end of the user field in your miner. It goes after the wallet address and the worker name:
YOUR_WALLET_ADDRESS.rig1=DIFFICULTYThe difficulty then stays fixed for as long as that connection lasts, and vardiff leaves it alone. A value below the pool's lowest difficulty is raised to it. One above its highest is lowered to it.
To go back to vardiff, remove the suffix and restart the miner.
What share difficulty does each HeroMiners pool use?
Pearl runs no vardiff. Every connection works at a fixed share difficulty of 2,097,152, the same for every rig. A difficulty added to the user field is ignored, and a bigger rig simply sends shares more often.
Quantus runs vardiff and aims for one share every 15 seconds. A new connection starts at 10,000,000,000. The difficulty stays between 1,000,000,000 and 1,000,000,000,000, and a static difficulty such as =20000000000 is held to the same range.
Qubitcoin runs vardiff and aims for one share every 30 seconds. A new connection starts at 32, and the difficulty stays between 32 and 10,000. A static difficulty such as =500 is held to the same range.