Quote from: A L I E N on June 03, 2013, 03:48:50 PM

Thanks.
Why does it adjust the difficulty and say "LONGPOLL from pool requested work restart" so often? Is that optimizing the hash rate? Should I set the difficulty with my username to reduce this?

This is normal p2pool behaviour. New work is set every time a share is found, which in our case is 30 seconds on average (10 seconds in BTC p2pool).

Quote from: mitty on April 18, 2013, 04:06:43 AM

The short version is that the work to produce the "next" block depends on the previous block. The moment a new block is found, any in-progress searching is aborted because it won't produce anything useful. This is important because it encourages a "found" block to be used and distributed quickly.

It might very briefly decrease your mining hashrate because of the time required to fetch new work from the pool/start working on the new work. It should be noted that p2pool has 10-second blocks so you'll see this message about once every 10 seconds. That's why you can't use p2pool with devices that take a long time to start new work like BFL singles.

Difficulty is adjusted every time a new share is found.

In any case, it is considered a good practice for miners with big hashrates to set their difficulty manually because it reduces p2pool's minimum share difficulty, helping small miners to achieve less variance. I would recommend tuning it in such way that your estimated time to share is several (5-10) times less than p2pool's time to block. So your difficulty can be calculated as

Code:

p2pool_difficulty * (your_hashrate / p2pool_hashrate) * (time_to_block / 30s) / 10

Details:https://bitcointalk.org/index.php?topic=18313.msg2060914#msg2060914