There are certain cases such as getblocktemplate which allow external
callers to be repsonsible for creating their own coinbase to replace the
generated one. By allowing the pay address to be nil in such cases, the
need to specify mining addresses via --miningaddr can be avoided thereby
leaving the payment address management up to the caller.
This commit implements a built-in concurrent CPU miner that can be enabled
with the combination of the --generate and --miningaddr options. The
--blockminsize, --blockmaxsize, and --blockprioritysize configuration
options wich already existed prior to this commit control the block
template generation and hence affect blocks mined via the new CPU miner.
The following is a quick overview of the changes and design:
- Starting btcd with --generate and no addresses specified via
--miningaddr will give an error and exit immediately
- Makes use of multiple worker goroutines which independently create block
templates, solve them, and submit the solved blocks
- The default number of worker threads are based on the number of
processor cores in the system and can be dynamically changed at
run-time
- There is a separate speed monitor goroutine used to collate periodic
updates from the workers to calculate overall hashing speed
- The current mining state, number of workers, and hashes per second can
be queried
- Updated sample-btcd.conf file has been updated to include the coin
generation (mining) settings
- Updated doc.go for the new command line options
In addition the old --getworkkey option is now deprecated in favor of the
new --miningaddr option. This was changed for a few reasons:
- There is no reason to have a separate list of keys for getwork and CPU
mining
- getwork is deprecated and will be going away in the future so that means
the --getworkkey flag will also be going away
- Having the work 'key' in the option can be confused with wanting a
private key while --miningaddr make it a little more clear it is an
address that is required
Closes#137.
Reviewed by @jrick.
