signet/miner: move next_block_* functions into new Generator class

This commit is contained in:
Anthony Towns 2022-10-01 11:25:01 +10:00
parent 35f4631196
commit 5540e6ca49

View file

@ -209,36 +209,46 @@ def seconds_to_hms(s):
out = "-" + out
return out
def next_block_delta(last_nbits, last_hash, ultimate_target, do_poisson, max_interval):
# strategy:
# 1) work out how far off our desired target we are
# 2) cap it to a factor of 4 since that's the best we can do in a single retarget period
# 3) use that to work out the desired average interval in this retarget period
# 4) if doing poisson, use the last hash to pick a uniformly random number in [0,1), and work out a random multiplier to vary the average by
# 5) cap the resulting interval between 1 second and 1 hour to avoid extremes
class Generate:
INTERVAL = 600.0*2016/2015 # 10 minutes, adjusted for the off-by-one bug
current_target = nbits_to_target(last_nbits)
retarget_factor = ultimate_target / current_target
retarget_factor = max(0.25, min(retarget_factor, 4.0))
avg_interval = INTERVAL * retarget_factor
def __init__(self, multiminer=None, ultimate_target=None, poisson=False, max_interval=1800):
if multiminer is None:
multiminer = (0, 1, 1)
(self.multi_low, self.multi_high, self.multi_period) = multiminer
self.ultimate_target = ultimate_target
self.poisson = poisson
self.max_interval = max_interval
if do_poisson:
det_rand = int(last_hash[-8:], 16) * 2**-32
this_interval_variance = -math.log1p(-det_rand)
else:
this_interval_variance = 1
def next_block_delta(self, last_nbits, last_hash):
# strategy:
# 1) work out how far off our desired target we are
# 2) cap it to a factor of 4 since that's the best we can do in a single retarget period
# 3) use that to work out the desired average interval in this retarget period
# 4) if doing poisson, use the last hash to pick a uniformly random number in [0,1), and work out a random multiplier to vary the average by
# 5) cap the resulting interval between 1 second and 1 hour to avoid extremes
this_interval = avg_interval * this_interval_variance
this_interval = max(1, min(this_interval, max_interval))
current_target = nbits_to_target(last_nbits)
retarget_factor = self.ultimate_target / current_target
retarget_factor = max(0.25, min(retarget_factor, 4.0))
return this_interval
avg_interval = self.INTERVAL * retarget_factor
def next_block_is_mine(last_hash, my_blocks):
det_rand = int(last_hash[-16:-8], 16)
return my_blocks[0] <= (det_rand % my_blocks[2]) < my_blocks[1]
if self.poisson:
det_rand = int(last_hash[-8:], 16) * 2**-32
this_interval_variance = -math.log1p(-det_rand)
else:
this_interval_variance = 1
this_interval = avg_interval * this_interval_variance
this_interval = max(1, min(this_interval, self.max_interval))
return this_interval
def next_block_is_mine(self, last_hash):
det_rand = int(last_hash[-16:-8], 16)
return self.multi_low <= (det_rand % self.multi_period) < self.multi_high
def do_generate(args):
if args.max_blocks is not None:
@ -298,6 +308,8 @@ def do_generate(args):
ultimate_target = nbits_to_target(int(args.nbits,16))
gen = Generate(multiminer=my_blocks, ultimate_target=ultimate_target, poisson=args.poisson, max_interval=args.max_interval)
mined_blocks = 0
bestheader = {"hash": None}
lastheader = None
@ -312,9 +324,9 @@ def do_generate(args):
if lastheader is None:
lastheader = bestheader["hash"]
elif bestheader["hash"] != lastheader:
next_delta = next_block_delta(int(bestheader["bits"], 16), bestheader["hash"], ultimate_target, args.poisson, args.max_interval)
next_delta = gen.next_block_delta(int(bestheader["bits"], 16), bestheader["hash"])
next_delta += bestheader["time"] - time.time()
next_is_mine = next_block_is_mine(bestheader["hash"], my_blocks)
next_is_mine = gen.next_block_is_mine(bestheader["hash"])
logging.info("Received new block at height %d; next in %s (%s)", bestheader["height"], seconds_to_hms(next_delta), ("mine" if next_is_mine else "backup"))
lastheader = bestheader["hash"]
@ -326,17 +338,17 @@ def do_generate(args):
action_time = now
is_mine = True
elif bestheader["height"] == 0:
time_delta = next_block_delta(int(bestheader["bits"], 16), bci["bestblockhash"], ultimate_target, args.poisson, args.max_interval)
time_delta = gen.next_block_delta(int(bestheader["bits"], 16), bci["bestblockhash"])
time_delta *= 100 # 100 blocks
logging.info("Backdating time for first block to %d minutes ago" % (time_delta/60))
mine_time = now - time_delta
action_time = now
is_mine = True
else:
time_delta = next_block_delta(int(bestheader["bits"], 16), bci["bestblockhash"], ultimate_target, args.poisson, args.max_interval)
time_delta = gen.next_block_delta(int(bestheader["bits"], 16), bci["bestblockhash"])
mine_time = bestheader["time"] + time_delta
is_mine = next_block_is_mine(bci["bestblockhash"], my_blocks)
is_mine = gen.next_block_is_mine(bci["bestblockhash"])
action_time = mine_time
if not is_mine:
@ -407,9 +419,9 @@ def do_generate(args):
# report
bstr = "block" if is_mine else "backup block"
next_delta = next_block_delta(block.nBits, block.hash, ultimate_target, args.poisson, args.max_interval)
next_delta = gen.next_block_delta(block.nBits, block.hash)
next_delta += block.nTime - time.time()
next_is_mine = next_block_is_mine(block.hash, my_blocks)
next_is_mine = gen.next_block_is_mine(block.hash)
logging.debug("Block hash %s payout to %s", block.hash, reward_addr)
logging.info("Mined %s at height %d; next in %s (%s)", bstr, tmpl["height"], seconds_to_hms(next_delta), ("mine" if next_is_mine else "backup"))