What exactly does difficulty do/mean?

Soappa

hero member

Activity: 569

Merit: 500

Quote from: Chrithu on May 27, 2014, 07:31:26 AM

I just wondered that. I see it increase and know it somehow makes mining harder to keep the blockrate at 10 minutes per block.

But how does it do it?

Does it

a) make it harder to create the actual hashes thus making the hardware take more time to create them?

or

b) increase the total number of hashes that can be created thus decreasing the percentile of the hashes that are valid for the current block?

A higher "difficulty" is associated with a lower "target". And a block is considered valid if it has a hash value lower than the target value.
So, it is less likely to get a valid block with each of your hashes when difficulty is higher.

For example, current difficulty is 10.45G (https://blockexplorer.com/q/getdifficulty).
The corresponding target (https://blockexplorer.com/q/hextarget) is

Code:

0000000000000000692842000000000000000000000000000000000000000000

So, the hash of all blocks find now need to be smaller than that value.
Block 302883 is:

Code:

00000000000000002fe31fd66a9d82b1e204d056b118f86a314af955d91f51c2

Block 302884 is:

Code:

00000000000000001921a0ebf2cf6684c37a620a68987cb945df8e87676b360f

Soappa

hero member

Activity: 569

Merit: 500

Quote from: tuanvie on May 27, 2014, 09:03:53 AM

whether to mine the miners crowded pool will quickly get results?
This has always been my question, and the opinion of my friend Huh

Joining a bigger pool won't increase your miner's hashrate or make your expected profit higher, but it will lower the variance of your profit.

tuanvie

sr. member

Activity: 448

Merit: 250

whether to mine the miners crowded pool will quickly get results?
This has always been my question, and the opinion of my friend Huh

DrG

legendary

Activity: 2086

Merit: 1035

It's more like B. You will notice CPUs will still make the same measly KH/s, GPUs still makes the same MH/s. But if you mine on a pool the shares they submit would be worth to nothing, less than 1 satoshi each. Some of the high end ASIC machines are putting out 100k hashes per minutes now which would make your classic 5830 cry Tongue

An easy anology would be every time the difficulty jumps it's like needing to pick an extra number to win a lottery. Picking 6 numbers is difficult. Picking 7 is even harder.

Chrithu

full member

Activity: 224

Merit: 100

I just wondered that. I see it increase and know it somehow makes mining harder to keep the blockrate at 10 minutes per block.

But how does it do it?

Does it

a) make it harder to create the actual hashes thus making the hardware take more time to create them?

or

b) increase the total number of hashes that can be created thus decreasing the percentile of the hashes that are valid for the current block?

Related question: Can hardware become outdated because it it will not be able to create hashes anymore as difficulty rises? Or does it's usefulness purely stem from the number of hashes it is able to create per timeframe?

Topic: What exactly does difficulty do/mean? (Read 633 times)