[T4] Rename all shiftsize / cuckoo_size to edge_bits and change value for T4 (#1752)

* replace all size_shift / cuckoo_size by edge_bits and change some constants for T4
* replace remaining occurrences of sizeshift

api/src/types.rs

@@ -502,7 +502,7 @@ pub struct BlockHeaderPrintable {
 	/// Nonce increment used to mine this block.
 	pub nonce: u64,
 	/// Size of the cuckoo graph
-	pub cuckoo_size: u8,
+	pub edge_bits: u8,
 	pub cuckoo_solution: Vec<u64>,
 	/// Total accumulated difficulty since genesis block
 	pub total_difficulty: u64,
@@ -522,7 +522,7 @@ impl BlockHeaderPrintable {
 			range_proof_root: util::to_hex(h.range_proof_root.to_vec()),
 			kernel_root: util::to_hex(h.kernel_root.to_vec()),
 			nonce: h.pow.nonce,
-			cuckoo_size: h.pow.cuckoo_sizeshift(),
+			edge_bits: h.pow.edge_bits(),
 			cuckoo_solution: h.pow.proof.nonces.clone(),
 			total_difficulty: h.pow.total_difficulty.to_num(),
 			total_kernel_offset: h.total_kernel_offset.to_hex(),

chain/src/error.rs

@@ -45,9 +45,9 @@ pub enum ErrorKind {
 	/// Addition of difficulties on all previous block is wrong
 	#[fail(display = "Addition of difficulties on all previous blocks is wrong")]
 	WrongTotalDifficulty,
-	/// Block header sizeshift is incorrect
+	/// Block header edge_bits is lower than our min
-	#[fail(display = "Cuckoo size shift is invalid")]
+	#[fail(display = "Cuckoo Size too small")]
-	InvalidSizeshift,
+	LowEdgebits,
 	/// Scaling factor between primary and secondary PoW is invalid
 	#[fail(display = "Wrong scaling factor")]
 	InvalidScaling,

chain/src/pipe.rs

@@ -371,13 +371,13 @@ fn validate_header(header: &BlockHeader, ctx: &mut BlockContext) -> Result<(), E
 
 	if !ctx.opts.contains(Options::SKIP_POW) {
 		if !header.pow.is_primary() && !header.pow.is_secondary() {
-			return Err(ErrorKind::InvalidSizeshift.into());
+			return Err(ErrorKind::LowEdgebits.into());
 		}
-		let shift = header.pow.cuckoo_sizeshift();
+		let edge_bits = header.pow.edge_bits();
-		if !(ctx.pow_verifier)(header, shift).is_ok() {
+		if !(ctx.pow_verifier)(header, edge_bits).is_ok() {
 			error!(
 				LOGGER,
-				"pipe: error validating header with cuckoo shift size {}", shift
+				"pipe: error validating header with cuckoo edge_bits {}", edge_bits
 			);
 			return Err(ErrorKind::InvalidPow.into());
 		}

chain/tests/data_file_integrity.rs

@@ -97,7 +97,7 @@ fn data_files() {
 				&mut b.header,
 				next_header_info.difficulty,
 				global::proofsize(),
-				global::min_sizeshift(),
+				global::min_edge_bits(),
 			).unwrap();
 
 			let _bhash = b.hash();

chain/tests/mine_simple_chain.rs

@@ -75,19 +75,19 @@ fn mine_empty_chain() {
 
 		chain.set_txhashset_roots(&mut b, false).unwrap();
 
-		let sizeshift = if n == 2 {
+		let edge_bits = if n == 2 {
-			global::min_sizeshift() + 1
+			global::min_edge_bits() + 1
 		} else {
-			global::min_sizeshift()
+			global::min_edge_bits()
 		};
-		b.header.pow.proof.cuckoo_sizeshift = sizeshift;
+		b.header.pow.proof.edge_bits = edge_bits;
 		pow::pow_size(
 			&mut b.header,
 			next_header_info.difficulty,
 			global::proofsize(),
-			sizeshift,
+			edge_bits,
 		).unwrap();
-		b.header.pow.proof.cuckoo_sizeshift = sizeshift;
+		b.header.pow.proof.edge_bits = edge_bits;
 
 		let bhash = b.hash();
 		chain.process_block(b, chain::Options::MINE).unwrap();
@@ -399,19 +399,19 @@ fn output_header_mappings() {
 
 		chain.set_txhashset_roots(&mut b, false).unwrap();
 
-		let sizeshift = if n == 2 {
+		let edge_bits = if n == 2 {
-			global::min_sizeshift() + 1
+			global::min_edge_bits() + 1
 		} else {
-			global::min_sizeshift()
+			global::min_edge_bits()
 		};
-		b.header.pow.proof.cuckoo_sizeshift = sizeshift;
+		b.header.pow.proof.edge_bits = edge_bits;
 		pow::pow_size(
 			&mut b.header,
 			next_header_info.difficulty,
 			global::proofsize(),
-			sizeshift,
+			edge_bits,
 		).unwrap();
-		b.header.pow.proof.cuckoo_sizeshift = sizeshift;
+		b.header.pow.proof.edge_bits = edge_bits;
 
 		chain.process_block(b, chain::Options::MINE).unwrap();
 

chain/tests/test_coinbase_maturity.rs

@@ -80,7 +80,7 @@ fn test_coinbase_maturity() {
 		&mut block.header,
 		next_header_info.difficulty,
 		global::proofsize(),
-		global::min_sizeshift(),
+		global::min_edge_bits(),
 	).unwrap();
 
 	assert_eq!(block.outputs().len(), 1);
@@ -137,7 +137,7 @@ fn test_coinbase_maturity() {
 		&mut block.header,
 		next_header_info.difficulty,
 		global::proofsize(),
-		global::min_sizeshift(),
+		global::min_edge_bits(),
 	).unwrap();
 
 	// mine enough blocks to increase the height sufficiently for
@@ -160,7 +160,7 @@ fn test_coinbase_maturity() {
 			&mut block.header,
 			next_header_info.difficulty,
 			global::proofsize(),
-			global::min_sizeshift(),
+			global::min_edge_bits(),
 		).unwrap();
 
 		chain.process_block(block, chain::Options::MINE).unwrap();
@@ -187,7 +187,7 @@ fn test_coinbase_maturity() {
 		&mut block.header,
 		next_header_info.difficulty,
 		global::proofsize(),
-		global::min_sizeshift(),
+		global::min_edge_bits(),
 	).unwrap();
 
 	let result = chain.process_block(block, chain::Options::MINE);

core/src/consensus.rs

@@ -62,19 +62,20 @@ pub fn secondary_pow_ratio(height: u64) -> u64 {
 /// Cuckoo-cycle proof size (cycle length)
 pub const PROOFSIZE: usize = 42;
 
-/// Default Cuckoo Cycle size shift used for mining and validating.
+/// Default Cuckoo Cycle edge_bits, used for mining and validating.
-pub const DEFAULT_MIN_SIZESHIFT: u8 = 30;
+pub const DEFAULT_MIN_EDGE_BITS: u8 = 30;
 
-/// Secondary proof-of-work size shift, meant to be ASIC resistant.
+/// Secondary proof-of-work edge_bits, meant to be ASIC resistant.
-pub const SECOND_POW_SIZESHIFT: u8 = 29;
+pub const SECOND_POW_EDGE_BITS: u8 = 29;
 
-/// Original reference sizeshift to compute difficulty factors for higher
+/// Original reference edge_bits to compute difficulty factors for higher
 /// Cuckoo graph sizes, changing this would hard fork
-pub const REFERENCE_SIZESHIFT: u8 = 30;
+pub const BASE_EDGE_BITS: u8 = 24;
 
-/// Default Cuckoo Cycle easiness, high enough to have good likeliness to find
+/// maximum scaling factor for secondary pow, enforced in diff retargetting
-/// a solution.
+/// increasing scaling factor increases frequency of secondary blocks
-pub const EASINESS: u32 = 50;
+/// ONLY IN TESTNET4 LIMITED TO ABOUT 8 TIMES THE NATURAL SCALE
+pub const MAX_SECOND_POW_SCALE: u64 = 8 << 11;
 
 /// Default number of blocks in the past when cross-block cut-through will start
 /// happening. Needs to be long enough to not overlap with a long reorg.

core/src/core/block.rs

@@ -158,11 +158,11 @@ fn fixed_size_of_serialized_header(_version: u16) -> usize {
 }
 
 /// Serialized size of a BlockHeader
-pub fn serialized_size_of_header(version: u16, cuckoo_sizeshift: u8) -> usize {
+pub fn serialized_size_of_header(version: u16, edge_bits: u8) -> usize {
 	let mut size = fixed_size_of_serialized_header(version);
 
-	size += mem::size_of::<u8>(); // pow.cuckoo_sizeshift
+	size += mem::size_of::<u8>(); // pow.edge_bits
-	let nonce_bits = cuckoo_sizeshift as usize - 1;
+	let nonce_bits = edge_bits as usize;
 	let bitvec_len = global::proofsize() * nonce_bits;
 	size += bitvec_len / 8; // pow.nonces
 	if bitvec_len % 8 != 0 {
@@ -306,8 +306,8 @@ impl BlockHeader {
 	pub fn serialized_size(&self) -> usize {
 		let mut size = fixed_size_of_serialized_header(self.version);
 
-		size += mem::size_of::<u8>(); // pow.cuckoo_sizeshift
+		size += mem::size_of::<u8>(); // pow.edge_bits
-		let nonce_bits = self.pow.cuckoo_sizeshift() as usize - 1;
+		let nonce_bits = self.pow.edge_bits() as usize;
 		let bitvec_len = global::proofsize() * nonce_bits;
 		size += bitvec_len / 8; // pow.nonces
 		if bitvec_len % 8 != 0 {

core/src/global.rs

@@ -18,12 +18,11 @@
 
 use consensus::HeaderInfo;
 use consensus::{
-	BLOCK_TIME_SEC, COINBASE_MATURITY, CUT_THROUGH_HORIZON, DEFAULT_MIN_SIZESHIFT,
+	BLOCK_TIME_SEC, COINBASE_MATURITY, CUT_THROUGH_HORIZON, DEFAULT_MIN_EDGE_BITS,
 	DIFFICULTY_ADJUST_WINDOW, INITIAL_DIFFICULTY, MEDIAN_TIME_WINDOW, PROOFSIZE,
-	REFERENCE_SIZESHIFT,
+	BASE_EDGE_BITS,
 };
 use pow::{self, CuckatooContext, EdgeType, PoWContext};
-
 /// An enum collecting sets of parameters used throughout the
 /// code wherever mining is needed. This should allow for
 /// different sets of parameters for different purposes,
@@ -33,14 +32,14 @@ use std::sync::RwLock;
 /// Define these here, as they should be developer-set, not really tweakable
 /// by users
 
-/// Automated testing sizeshift
+/// Automated testing edge_bits
-pub const AUTOMATED_TESTING_MIN_SIZESHIFT: u8 = 10;
+pub const AUTOMATED_TESTING_MIN_EDGE_BITS: u8 = 9;
 
 /// Automated testing proof size
 pub const AUTOMATED_TESTING_PROOF_SIZE: usize = 4;
 
-/// User testing sizeshift
+/// User testing edge_bits
-pub const USER_TESTING_MIN_SIZESHIFT: u8 = 19;
+pub const USER_TESTING_MIN_EDGE_BITS: u8 = 15;
 
 /// User testing proof size
 pub const USER_TESTING_PROOF_SIZE: usize = 42;
@@ -147,27 +146,27 @@ pub fn pow_type() -> PoWContextTypes {
 	PoWContextTypes::Cuckatoo
 }
 
-/// The minimum acceptable sizeshift
+/// The minimum acceptable edge_bits
-pub fn min_sizeshift() -> u8 {
+pub fn min_edge_bits() -> u8 {
 	let param_ref = CHAIN_TYPE.read().unwrap();
 	match *param_ref {
-		ChainTypes::AutomatedTesting => AUTOMATED_TESTING_MIN_SIZESHIFT,
+		ChainTypes::AutomatedTesting => AUTOMATED_TESTING_MIN_EDGE_BITS,
-		ChainTypes::UserTesting => USER_TESTING_MIN_SIZESHIFT,
+		ChainTypes::UserTesting => USER_TESTING_MIN_EDGE_BITS,
-		ChainTypes::Testnet1 => USER_TESTING_MIN_SIZESHIFT,
+		ChainTypes::Testnet1 => USER_TESTING_MIN_EDGE_BITS,
-		_ => DEFAULT_MIN_SIZESHIFT,
+		_ => DEFAULT_MIN_EDGE_BITS,
 	}
 }
 
-/// Reference sizeshift used to compute factor on higher Cuckoo graph sizes,
+/// Reference edge_bits used to compute factor on higher Cuck(at)oo graph sizes,
-/// while the min_sizeshift can be changed on a soft fork, changing
+/// while the min_edge_bits can be changed on a soft fork, changing
-/// ref_sizeshift is a hard fork.
+/// base_edge_bits is a hard fork.
-pub fn ref_sizeshift() -> u8 {
+pub fn base_edge_bits() -> u8 {
 	let param_ref = CHAIN_TYPE.read().unwrap();
 	match *param_ref {
-		ChainTypes::AutomatedTesting => AUTOMATED_TESTING_MIN_SIZESHIFT,
+		ChainTypes::AutomatedTesting => AUTOMATED_TESTING_MIN_EDGE_BITS,
-		ChainTypes::UserTesting => USER_TESTING_MIN_SIZESHIFT,
+		ChainTypes::UserTesting => USER_TESTING_MIN_EDGE_BITS,
-		ChainTypes::Testnet1 => USER_TESTING_MIN_SIZESHIFT,
+		ChainTypes::Testnet1 => USER_TESTING_MIN_EDGE_BITS,
-		_ => REFERENCE_SIZESHIFT,
+		_ => BASE_EDGE_BITS,
 	}
 }
 
@@ -250,9 +249,9 @@ pub fn get_genesis_nonce() -> u64 {
 	match *param_ref {
 		// won't make a difference
 		ChainTypes::AutomatedTesting => 0,
-		// Magic nonce for current genesis block at cuckoo16
+		// Magic nonce for current genesis block at cuckatoo15
 		ChainTypes::UserTesting => 27944,
-		// Magic nonce for genesis block for testnet2 (cuckoo30)
+		// Magic nonce for genesis block for testnet2 (cuckatoo29)
 		_ => panic!("Pre-set"),
 	}
 }

core/src/pow/common.rs

@@ -130,7 +130,7 @@ macro_rules! to_edge {
 }
 
 /// Utility struct to calculate commonly used Cuckoo parameters calculated
-/// from header, nonce, sizeshift, etc.
+/// from header, nonce, edge_bits, etc.
 pub struct CuckooParams<T>
 where
 	T: EdgeType,

core/src/pow/cuckoo.rs

@@ -246,7 +246,7 @@ where
 			match sol {
 				Ok(s) => {
 					let mut proof = Proof::new(map_vec!(s.to_vec(), |&n| n.to_u64().unwrap_or(0)));
-					proof.cuckoo_sizeshift = self.params.edge_bits;
+					proof.edge_bits = self.params.edge_bits;
 					return Ok(vec![proof]);
 				}
 				Err(e) => match e.kind() {
@@ -398,21 +398,21 @@ mod test {
 		cuckoo_ctx.set_header_nonce(header.clone(), Some(39), true)?;
 		let res = cuckoo_ctx.find_cycles()?;
 		let mut proof = Proof::new(V1.to_vec());
-		proof.cuckoo_sizeshift = 20;
+		proof.edge_bits = 20;
 		assert_eq!(proof, res[0]);
 
 		let mut cuckoo_ctx = CuckooContext::<T>::new(20, 42, 10)?;
 		cuckoo_ctx.set_header_nonce(header.clone(), Some(56), true)?;
 		let res = cuckoo_ctx.find_cycles()?;
 		let mut proof = Proof::new(V2.to_vec());
-		proof.cuckoo_sizeshift = 20;
+		proof.edge_bits = 20;
 		assert_eq!(proof, res[0]);
 
 		//re-use context
 		cuckoo_ctx.set_header_nonce(header, Some(66), true)?;
 		let res = cuckoo_ctx.find_cycles()?;
 		let mut proof = Proof::new(V3.to_vec());
-		proof.cuckoo_sizeshift = 20;
+		proof.edge_bits = 20;
 		assert_eq!(proof, res[0]);
 		Ok(())
 	}

core/src/pow/mod.rs

@@ -79,7 +79,7 @@ pub fn mine_genesis_block() -> Result<Block, Error> {
 	// total_difficulty on the genesis header *is* the difficulty of that block
 	let genesis_difficulty = gen.header.pow.total_difficulty.clone();
 
-	let sz = global::min_sizeshift();
+	let sz = global::min_edge_bits();
 	let proof_size = global::proofsize();
 
 	pow_size(&mut gen.header, genesis_difficulty, proof_size, sz)?;
@@ -143,10 +143,10 @@ mod test {
 			&mut b.header,
 			Difficulty::one(),
 			global::proofsize(),
-			global::min_sizeshift(),
+			global::min_edge_bits(),
 		).unwrap();
 		assert!(b.header.pow.nonce != 310);
 		assert!(b.header.pow.to_difficulty() >= Difficulty::one());
-		assert!(verify_size(&b.header, global::min_sizeshift()).is_ok());
+		assert!(verify_size(&b.header, global::min_edge_bits()).is_ok());
 	}
 }

core/src/pow/types.rs

@@ -21,7 +21,7 @@ use std::{fmt, iter};
 use rand::{thread_rng, Rng};
 use serde::{de, Deserialize, Deserializer, Serialize, Serializer};
 
-use consensus::SECOND_POW_SIZESHIFT;
+use consensus::SECOND_POW_EDGE_BITS;
 use core::hash::Hashed;
 use global;
 use ser::{self, Readable, Reader, Writeable, Writer};
@@ -80,16 +80,20 @@ impl Difficulty {
 		Difficulty { num: max(num, 1) }
 	}
 
+	/// Compute difficulty scaling factor for graph defined by 2 * 2^edge_bits * edge_bits bits
+	pub fn scale(edge_bits: u8) -> u64 {
+		(2 << (edge_bits - global::base_edge_bits()) as u64) * (edge_bits as u64)
+	}
+
 	/// Computes the difficulty from a hash. Divides the maximum target by the
-	/// provided hash and applies the Cuckoo sizeshift adjustment factor (see
+	/// provided hash and applies the Cuck(at)oo size adjustment factor (see
 	/// https://lists.launchpad.net/mimblewimble/msg00494.html).
 	fn from_proof_adjusted(proof: &Proof) -> Difficulty {
 		// Adjust the difficulty based on a 2^(N-M)*(N-1) factor, with M being
-		// the minimum sizeshift and N the provided sizeshift
+		// the minimum edge_bits and N the provided edge_bits
-		let shift = proof.cuckoo_sizeshift;
+		let edge_bits = proof.edge_bits;
-		let adjust_factor = (1 << (shift - global::ref_sizeshift()) as u64) * (shift as u64 - 1);
 
-		Difficulty::from_num(proof.raw_difficulty() * adjust_factor)
+		Difficulty::from_num(proof.raw_difficulty() * Difficulty::scale(edge_bits))
 	}
 
 	/// Same as `from_proof_adjusted` but instead of an adjustment based on
@@ -277,38 +281,38 @@ impl ProofOfWork {
 	pub fn to_difficulty(&self) -> Difficulty {
 		// 2 proof of works, Cuckoo29 (for now) and Cuckoo30+, which are scaled
 		// differently (scaling not controlled for now)
-		if self.proof.cuckoo_sizeshift == SECOND_POW_SIZESHIFT {
+		if self.proof.edge_bits == SECOND_POW_EDGE_BITS {
 			Difficulty::from_proof_scaled(&self.proof, self.scaling_difficulty)
 		} else {
 			Difficulty::from_proof_adjusted(&self.proof)
 		}
 	}
 
-	/// The shift used for the cuckoo cycle size on this proof
+	/// The edge_bits used for the cuckoo cycle size on this proof
-	pub fn cuckoo_sizeshift(&self) -> u8 {
+	pub fn edge_bits(&self) -> u8 {
-		self.proof.cuckoo_sizeshift
+		self.proof.edge_bits
 	}
 
 	/// Whether this proof of work is for the primary algorithm (as opposed
-	/// to secondary). Only depends on the size shift at this time.
+	/// to secondary). Only depends on the edge_bits at this time.
 	pub fn is_primary(&self) -> bool {
 		// 2 conditions are redundant right now but not necessarily in
 		// the future
-		self.proof.cuckoo_sizeshift != SECOND_POW_SIZESHIFT
+		self.proof.edge_bits != SECOND_POW_EDGE_BITS
-			&& self.proof.cuckoo_sizeshift >= global::min_sizeshift()
+			&& self.proof.edge_bits >= global::min_edge_bits()
 	}
 
 	/// Whether this proof of work is for the secondary algorithm (as opposed
-	/// to primary). Only depends on the size shift at this time.
+	/// to primary). Only depends on the edge_bits at this time.
 	pub fn is_secondary(&self) -> bool {
-		self.proof.cuckoo_sizeshift == SECOND_POW_SIZESHIFT
+		self.proof.edge_bits == SECOND_POW_EDGE_BITS
 	}
 }
 
-/// A Cuckoo Cycle proof of work, consisting of the shift to get the graph
+/// A Cuck(at)oo Cycle proof of work, consisting of the edge_bits to get the graph
-/// size (i.e. 31 for Cuckoo31 with a 2^31 or 1<<31 graph size) and the nonces
+/// size (i.e. the 2-log of the number of edges) and the nonces
-/// of the graph solution. While being expressed as u64 for simplicity, each
+/// of the graph solution. While being expressed as u64 for simplicity,
-/// nonce is strictly less than half the cycle size (i.e. <2^30 for Cuckoo 31).
+/// nonces a.k.a. edge indices range from 0 to (1 << edge_bits) - 1
 ///
 /// The hash of the `Proof` is the hash of its packed nonces when serializing
 /// them at their exact bit size. The resulting bit sequence is padded to be
@@ -317,14 +321,14 @@ impl ProofOfWork {
 #[derive(Clone, PartialOrd, PartialEq)]
 pub struct Proof {
 	/// Power of 2 used for the size of the cuckoo graph
-	pub cuckoo_sizeshift: u8,
+	pub edge_bits: u8,
 	/// The nonces
 	pub nonces: Vec<u64>,
 }
 
 impl fmt::Debug for Proof {
 	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-		write!(f, "Cuckoo{}(", self.cuckoo_sizeshift)?;
+		write!(f, "Cuckoo{}(", self.edge_bits)?;
 		for (i, val) in self.nonces[..].iter().enumerate() {
 			write!(f, "{:x}", val)?;
 			if i < self.nonces.len() - 1 {
@@ -338,11 +342,11 @@ impl fmt::Debug for Proof {
 impl Eq for Proof {}
 
 impl Proof {
-	/// Builds a proof with provided nonces at default sizeshift
+	/// Builds a proof with provided nonces at default edge_bits
 	pub fn new(mut in_nonces: Vec<u64>) -> Proof {
 		in_nonces.sort();
 		Proof {
-			cuckoo_sizeshift: global::min_sizeshift(),
+			edge_bits: global::min_edge_bits(),
 			nonces: in_nonces,
 		}
 	}
@@ -350,7 +354,7 @@ impl Proof {
 	/// Builds a proof with all bytes zeroed out
 	pub fn zero(proof_size: usize) -> Proof {
 		Proof {
-			cuckoo_sizeshift: global::min_sizeshift(),
+			edge_bits: global::min_edge_bits(),
 			nonces: vec![0; proof_size],
 		}
 	}
@@ -359,17 +363,17 @@ impl Proof {
 	/// needed so that tests that ignore POW
 	/// don't fail due to duplicate hashes
 	pub fn random(proof_size: usize) -> Proof {
-		let sizeshift = global::min_sizeshift();
+		let edge_bits = global::min_edge_bits();
-		let nonce_mask = (1 << (sizeshift - 1)) - 1;
+		let nonce_mask = (1 << edge_bits) - 1;
 		let mut rng = thread_rng();
-		// force the random num to be within sizeshift bits
+		// force the random num to be within edge_bits bits
 		let mut v: Vec<u64> = iter::repeat(())
 			.map(|()| (rng.gen::<u32>() & nonce_mask) as u64)
 			.take(proof_size)
 			.collect();
 		v.sort();
 		Proof {
-			cuckoo_sizeshift: global::min_sizeshift(),
+			edge_bits: global::min_edge_bits(),
 			nonces: v,
 		}
 	}
@@ -387,16 +391,13 @@ impl Proof {
 
 impl Readable for Proof {
 	fn read(reader: &mut Reader) -> Result<Proof, ser::Error> {
-		let cuckoo_sizeshift = reader.read_u8()?;
+		let edge_bits = reader.read_u8()?;
-		if cuckoo_sizeshift == 0 || cuckoo_sizeshift > 64 {
+		if edge_bits == 0 || edge_bits > 64 {
 			return Err(ser::Error::CorruptedData);
 		}
 
 		let mut nonces = Vec::with_capacity(global::proofsize());
-		let mut nonce_bits = cuckoo_sizeshift as usize;
+		let nonce_bits = edge_bits as usize;
-		if global::pow_type() == global::PoWContextTypes::Cuckoo {
-			nonce_bits -= 1;
-		}
 		let bytes_len = BitVec::bytes_len(nonce_bits * global::proofsize());
 		let bits = reader.read_fixed_bytes(bytes_len)?;
 		let bitvec = BitVec { bits };
@@ -410,7 +411,7 @@ impl Readable for Proof {
 			nonces.push(nonce);
 		}
 		Ok(Proof {
-			cuckoo_sizeshift,
+			edge_bits,
 			nonces,
 		})
 	}
@@ -419,13 +420,9 @@ impl Readable for Proof {
 impl Writeable for Proof {
 	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ser::Error> {
 		if writer.serialization_mode() != ser::SerializationMode::Hash {
-			writer.write_u8(self.cuckoo_sizeshift)?;
+			writer.write_u8(self.edge_bits)?;
-		}
-
-		let mut nonce_bits = self.cuckoo_sizeshift as usize;
-		if global::pow_type() == global::PoWContextTypes::Cuckoo {
-			nonce_bits -= 1;
 		}
+		let nonce_bits = self.edge_bits as usize;
 		let mut bitvec = BitVec::new(nonce_bits * global::proofsize());
 		for (n, nonce) in self.nonces.iter().enumerate() {
 			for bit in 0..nonce_bits {

doc/api/node_api.md

@@ -78,7 +78,7 @@ Optionally return results as "compact blocks" by passing `?compact` query.
     | - range_proof_root    | string   | Merklish root of all range proofs in the TxHashSet                          |
     | - kernel_root         | string   | Merklish root of all transaction kernels in the TxHashSet                   |
     | - nonce               | number   | Nonce increment used to mine this block                                     |
-    | - cuckoo_size         | number   | Size of the cuckoo graph                                                    |
+    | - edge_bits           | number   | Size of the cuckoo graph (2_log of number of edges)                         |
     | - cuckoo_solution     | []number | The Cuckoo solution for this block                                          |
     | - total_difficulty    | number   | Total accumulated difficulty since genesis block                            |
     | - total_kernel_offset | string   | Total kernel offset since genesis block                                     |
@@ -163,7 +163,7 @@ Returns data about a block headers given either a hash or height or an output co
     | - range_proof_root    | string   | Merklish root of all range proofs in the TxHashSet                          |
     | - kernel_root         | string   | Merklish root of all transaction kernels in the TxHashSet                   |
     | - nonce               | number   | Nonce increment used to mine this block                                     |
-    | - cuckoo_size         | number   | Size of the cuckoo graph                                                    |
+    | - edge_bits           | number   | Size of the cuckoo graph (2_log of number of edges)                         |
     | - cuckoo_solution     | []number | The Cuckoo solution for this block                                          |
     | - total_difficulty    | number   | Total accumulated difficulty since genesis block                            |
     | - total_kernel_offset | string   | Total kernel offset since genesis block                                     |
@@ -1146,4 +1146,4 @@ Retrieves information about a specific peer.
         console.log(r);
       }
     });
-  ```
+  ```

p2p/src/protocol.rs

@@ -335,9 +335,9 @@ fn headers_header_size(conn: &mut TcpStream, msg_len: u64) -> Result<u64, Error>
 	}
 	let average_header_size = (msg_len - 2) / total_headers;
 
-	// support size of Cuckoo: from Cuckoo 30 to Cuckoo 36, with version 2
+	// support size of Cuck(at)oo: from Cuck(at)oo 29 to Cuck(at)oo 35, with version 2
 	// having slightly larger headers
-	let min_size = core::serialized_size_of_header(1, global::min_sizeshift());
+	let min_size = core::serialized_size_of_header(1, global::min_edge_bits());
 	let max_size = min_size + 6;
 	if average_header_size < min_size as u64 || average_header_size > max_size as u64 {
 		debug!(

servers/src/common/stats.rs

@@ -19,6 +19,8 @@ use std::sync::atomic::AtomicBool;
 use std::sync::{Arc, RwLock};
 use std::time::SystemTime;
 
+use core::pow::Difficulty;
+
 use chrono::prelude::*;
 
 use chain;
@@ -98,7 +100,7 @@ pub struct StratumStats {
 	/// current network difficulty we're working on
 	pub network_difficulty: u64,
 	/// cuckoo size used for mining
-	pub cuckoo_size: u16,
+	pub edge_bits: u16,
 	/// Individual worker status
 	pub worker_stats: Vec<WorkerStats>,
 }
@@ -153,7 +155,7 @@ pub struct PeerStats {
 impl StratumStats {
 	/// Calculate network hashrate
 	pub fn network_hashrate(&self) -> f64 {
-		42.0 * (self.network_difficulty as f64 / (self.cuckoo_size - 1) as f64) / 60.0
+		42.0 * (self.network_difficulty as f64 / Difficulty::scale(self.edge_bits as u8) as f64) / 60.0
 	}
 }
 
@@ -207,7 +209,7 @@ impl Default for StratumStats {
 			num_workers: 0,
 			block_height: 0,
 			network_difficulty: 1000,
-			cuckoo_size: 30,
+			edge_bits: 29,
 			worker_stats: Vec::new(),
 		}
 	}

servers/src/grin/server.rs

@@ -313,7 +313,7 @@ impl Server {
 
 	/// Start a minimal "stratum" mining service on a separate thread
 	pub fn start_stratum_server(&self, config: StratumServerConfig) {
-		let cuckoo_size = global::min_sizeshift();
+		let edge_bits = global::min_edge_bits();
 		let proof_size = global::proofsize();
 		let sync_state = self.sync_state.clone();
 
@@ -327,7 +327,7 @@ impl Server {
 		let _ = thread::Builder::new()
 			.name("stratum_server".to_string())
 			.spawn(move || {
-				stratum_server.run_loop(stratum_stats, cuckoo_size as u32, proof_size, sync_state);
+				stratum_server.run_loop(stratum_stats, edge_bits as u32, proof_size, sync_state);
 			});
 	}
 

servers/src/mining/stratumserver.rs

@@ -75,7 +75,7 @@ struct SubmitParams {
 	height: u64,
 	job_id: u64,
 	nonce: u64,
-	cuckoo_size: u32,
+	edge_bits: u32,
 	pow: Vec<u64>,
 }
 
@@ -481,7 +481,7 @@ impl StratumServer {
 		}
 		let mut b: Block = b.unwrap().clone();
 		// Reconstruct the block header with this nonce and pow added
-		b.header.pow.proof.cuckoo_sizeshift = params.cuckoo_size as u8;
+		b.header.pow.proof.edge_bits = params.edge_bits as u8;
 		b.header.pow.nonce = params.nonce;
 		b.header.pow.proof.nonces = params.pow;
 		// Get share difficulty
@@ -532,7 +532,7 @@ impl StratumServer {
 			);
 		} else {
 			// Do some validation but dont submit
-			if !pow::verify_size(&b.header, b.header.pow.proof.cuckoo_sizeshift).is_ok() {
+			if !pow::verify_size(&b.header, b.header.pow.proof.edge_bits).is_ok() {
 				// Return error status
 				error!(
 					LOGGER,
@@ -653,15 +653,15 @@ impl StratumServer {
 	pub fn run_loop(
 		&mut self,
 		stratum_stats: Arc<RwLock<StratumStats>>,
-		cuckoo_size: u32,
+		edge_bits: u32,
 		proof_size: usize,
 		sync_state: Arc<SyncState>,
 	) {
 		info!(
 			LOGGER,
-			"(Server ID: {}) Starting stratum server with cuckoo_size = {}, proof_size = {}",
+			"(Server ID: {}) Starting stratum server with edge_bits = {}, proof_size = {}",
 			self.id,
-			cuckoo_size,
+			edge_bits,
 			proof_size
 		);
 
@@ -693,7 +693,7 @@ impl StratumServer {
 		{
 			let mut stratum_stats = stratum_stats.write().unwrap();
 			stratum_stats.is_running = true;
-			stratum_stats.cuckoo_size = cuckoo_size as u16;
+			stratum_stats.edge_bits = edge_bits as u16;
 		}
 
 		warn!(

servers/src/mining/test_miner.rs

@@ -87,7 +87,7 @@ impl Miner {
 			LOGGER,
 			"(Server ID: {}) Mining Cuckoo{} for max {}s on {} @ {} [{}].",
 			self.debug_output_id,
-			global::min_sizeshift(),
+			global::min_edge_bits(),
 			attempt_time_per_block,
 			b.header.total_difficulty(),
 			b.header.height,
@@ -97,7 +97,7 @@ impl Miner {
 
 		while head.hash() == *latest_hash && Utc::now().timestamp() < deadline {
 			let mut ctx =
-				global::create_pow_context::<u32>(global::min_sizeshift(), global::proofsize(), 10)
+				global::create_pow_context::<u32>(global::min_edge_bits(), global::proofsize(), 10)
 					.unwrap();
 			ctx.set_header_nonce(b.header.pre_pow(), None, true)
 				.unwrap();

src/bin/tui/mining.rs

@@ -217,7 +217,7 @@ impl TUIStatusListener for TUIMiningView {
 			)
 			.child(
 				LinearLayout::new(Orientation::Horizontal)
-					.child(TextView::new("  ").with_id("stratum_cuckoo_size_status")),
+					.child(TextView::new("  ").with_id("stratum_edge_bits_status")),
 			);
 
 		let mining_device_view = LinearLayout::new(Orientation::Vertical)
@@ -320,7 +320,7 @@ impl TUIStatusListener for TUIMiningView {
 		let stratum_block_height = format!("Solving Block Height: {}", stratum_stats.block_height);
 		let stratum_network_difficulty =
 			format!("Network Difficulty: {}", stratum_stats.network_difficulty);
-		let stratum_cuckoo_size = format!("Cuckoo Size: {}", stratum_stats.cuckoo_size);
+		let stratum_edge_bits = format!("Cuckoo Size: {}", stratum_stats.edge_bits);
 
 		c.call_on_id("stratum_config_status", |t: &mut TextView| {
 			t.set_content(stratum_enabled);
@@ -340,8 +340,8 @@ impl TUIStatusListener for TUIMiningView {
 		c.call_on_id("stratum_network_hashrate", |t: &mut TextView| {
 			t.set_content(stratum_network_hashrate);
 		});
-		c.call_on_id("stratum_cuckoo_size_status", |t: &mut TextView| {
+		c.call_on_id("stratum_edge_bits_status", |t: &mut TextView| {
-			t.set_content(stratum_cuckoo_size);
+			t.set_content(stratum_edge_bits);
 		});
 		let _ = c.call_on_id(
 			TABLE_MINING_STATUS,

src/bin/tui/status.rs

@@ -201,7 +201,7 @@ impl TUIStatusListener for TUIStatusView {
 						),
 						format!(
 							"Cuckoo {} - Network Difficulty {}",
-							stats.mining_stats.cuckoo_size,
+							stats.mining_stats.edge_bits,
 							stats.mining_stats.network_difficulty.to_string()
 						),
 					)

wallet/tests/common/mod.rs

@@ -103,7 +103,7 @@ pub fn add_block_with_reward(chain: &Chain, txs: Vec<&Transaction>, reward: CbDa
 		&mut b.header,
 		next_header_info.difficulty,
 		global::proofsize(),
-		global::min_sizeshift(),
+		global::min_edge_bits(),
 	).unwrap();
 	chain.process_block(b, chain::Options::MINE).unwrap();
 	chain.validate(false).unwrap();