How should you choose a pool?
First, let's go here and explore aspects of each pool (this may not be inclusive of all pools):
https://en.bitcoin.it/wiki/Comparison_of_mining_poolsConsiderations:Are you risk-averse or more likely to gamble?Bitcoin mining and block-hash solving is like a lottery, especially with the current high difficulty. With a high-end video card, Bitcoin mining by yourself will average you a 50 BTC block-find about every six months, but it better to think of it as a 4% chance of winning 50 BTC in a week. For many, this "gambling" is not acceptable, even though it would have the highest long-term payout, since you keep all generated earnings.
Pooled mining allows users to pool their resources together for smaller, but more regular payouts, similar to the office buying 100 lottery tickets and splitting the winnings. A higher pool hashrate means more regular but smaller payments. Are you fine with only getting a payment once every few days or even weeks on a small pool, even if that payment is still proportional to your work?
Lastly is pay-per-share pools, better described as "mining-for-hire". They pay you a fixed rate for your mining and accept the risk themselves, but typically with higher fees.
Will your earnings be reduced by pool-hopping?Proportional pools, and to a lesser extent, some math formula-based pools, can be gamed so that strategic timing of work submission will earn a miner more than others, and at other's expense. Is the payment method used by the pool impossible to exploit by hopping? (examples: PPS, PPLNS.) If a pool is using an exploitable rewards system, one must review if the pool has taken proactive and effective measures such as delaying statistics or setting policies to detect and ban pool hoppers. A pool's
hashrate graph often reveal the extent of pool hopping; if hashrate jumps up at the start of new rounds, that's probably bad for you. Conversely, if you are you a pool hopper you want a pool that can earn you the maximum gains for your work, by being undefended or even pool-hopper friendly.
Are the pool fees reasonable and competitive?A block solve currently generates a 50 BTC reward, plus the miner also earns the transaction fees Bitcoin users pay (which currenlty average about 0.2 BTC). Most pools keep the transaction fees for themselves, but some pay them out to users. Some pools are no fee, whereas others are up to 3%, only paying out 48.5 BTC to users upon a block solve. Some pools solicit for automatic donations, others will offer extra features when you opt for a higher donation level. You should weigh the fees when choosing a pool.
Does the pool have extra features you want?The simplest type of pool interface might be
Eligius, where you simply mine with your bitcoin address as a password, and earnings are paid out to the address. Pools greatly vary in features that benefit usability and convenience. Such features may include mining statistics and graphs for each video card, email notifications of payments or dead miners, automatic payouts at certain levels, user API for retrieving statistics, and more. Many users find particular features useful enough that this is a deciding factor.
Pool gimmicksDoes having features such as teams or affiliate/referral programs interest you? For some this might be a way to earn more, for others, this is a turn off due to the perception that it creates spam and that these rewards may be paid from the potential rewards of others. Some pools may offer bonuses or prizes for top earners or block finders, especially to promote a new pool. These might be an incentive where you can earn more, but one must also examine if they are sustainable or seem fair to all miners (or if they will even be paid...)
ReliabilityUptime and connectivity matters a lot. Look at pool forum threads and see if users have noted downtime or periods where work wasn't being accepted. Have users noted unsatisfactory "rejected share" or "efficiency" statistics? Did the pool respond and rectify reported issue? Was a downtime from a network DDoS attack, and was the pool able to rectify the attack vector? Does the pool support long-polling, a feature that reduces stale shares by promptly notifying mining software of a new block?
ReputationYou are trusting a pool operator with your earnings, to fairly account and properly distribute the BTC you mined, so the reputation and identity of the pool operator or organization counts for a lot. I find the web page design and information available there, and the amount of "used-car-salesmanship" says a lot. Is the pool operator well known through their forum profile and elsewhere, and do they seem competent to address the issues inherent in running a pool? Has the pool been around, can you easily contact pool operators or other pool members for support? If the pool disappeared tomorrow, how much risk would you as a user be taking?
My helpful hint - you don't have to just use one pool! Running two software miners per GPU, each using different pools, can give you more regular payments, and also will mitigate against downtime on one pool.Merged MiningTo support the alternate currency
Namecoin, the ability to mine two Bitcoin-like blockchains at once was created. Some pools support this, where you can earn in two different currencies at the same time. At current Namecoin
exchange rates, for example, you can earn 0.9% more at a pool that mines both.
update 2011-12-20/v1.2
