feat(remove): Temporally remove the internal miner functionality (#8184)

* remove functionality of internal miner

* fix configs

* fix typo in comment

* typo

Co-authored-by: Arya <aryasolhi@gmail.com>

* remove internal config for tests to pass

* typo

---------

Co-authored-by: Arya <aryasolhi@gmail.com>

Cargo.lock

@@ -1369,16 +1369,6 @@ dependencies = [
  "byteorder",
 ]
 
-[[package]]
-name = "equihash"
-version = "0.2.0"
-source = "git+https://github.com/ZcashFoundation/librustzcash.git?branch=equihash-solver-tromp#aff6fac6cb9c7390565313733f0ba7d679166504"
-dependencies = [
- "blake2b_simd",
- "byteorder",
- "cc",
-]
-
 [[package]]
 name = "equivalent"
 version = "1.0.1"
@@ -5584,7 +5574,7 @@ dependencies = [
  "blake2s_simd",
  "bls12_381",
  "byteorder",
- "equihash 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "equihash",
  "ff",
  "fpe",
  "group",
@@ -5682,8 +5672,7 @@ dependencies = [
  "criterion",
  "displaydoc",
  "ed25519-zebra",
- "equihash 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "equihash",
- "equihash 0.2.0 (git+https://github.com/ZcashFoundation/librustzcash.git?branch=equihash-solver-tromp)",
  "futures",
  "group",
  "halo2_proofs",

zebra-chain/Cargo.toml

@@ -35,12 +35,10 @@ getblocktemplate-rpcs = [
 ]
 
 # Experimental internal miner support
-internal-miner = [
+# TODO: Internal miner feature functionality was removed at https://github.com/ZcashFoundation/zebra/issues/8180
-    # TODO: replace with "equihash/solver" when that feature is merged and released:
+#       See what was removed at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-chain/Cargo.toml#L38-L43
-    # https://github.com/zcash/librustzcash/pull/1083
+#       Restore support when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
-    # https://github.com/zcash/librustzcash/pull/1088
+internal-miner = []
-    "equihash-solver",
-]
 
 # Experimental elasticsearch support
 elasticsearch = []
@@ -70,19 +68,10 @@ bridgetree = "0.4.0"
 bs58 = { version = "0.5.0", features = ["check"] }
 byteorder = "1.5.0"
 
+# TODO: Internal miner feature functionality was removed at https://github.com/ZcashFoundation/zebra/issues/8180
+#       See what was removed at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-chain/Cargo.toml#L73-L85
+#       Restore support when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
 equihash = "0.2.0"
-# Experimental internal miner support
-#
-# TODO: remove "equihash-solver" when the "equihash/solver" feature is merged and released:
-# https://github.com/zcash/librustzcash/pull/1083
-# https://github.com/zcash/librustzcash/pull/1088
-#
-# Use the solver PR:
-# - latest: branch = "equihash-solver-tromp",
-# - crashing with double-frees: rev = "da26c34772f4922eb13b4a1e7d88a969bbcf6a91",
-equihash-solver = { version = "0.2.0", git = "https://github.com/ZcashFoundation/librustzcash.git", branch = "equihash-solver-tromp", features = ["solver"], package = "equihash", optional = true }
-# or during development, use the locally checked out and modified version of equihash:
-#equihash-solver = { version = "0.2.0", path = "../../librustzcash/components/equihash", features = ["solver"], package = "equihash", optional = true }
 
 group = "0.13.0"
 incrementalmerkletree = "0.5.0"

zebra-chain/src/work/equihash.rs

@@ -106,93 +106,22 @@ impl Solution {
     #[cfg(feature = "internal-miner")]
     #[allow(clippy::unwrap_in_result)]
     pub fn solve<F>(
-        mut header: Header,
+        mut _header: Header,
-        mut cancel_fn: F,
+        mut _cancel_fn: F,
     ) -> Result<AtLeastOne<Header>, SolverCancelled>
     where
         F: FnMut() -> Result<(), SolverCancelled>,
     {
-        use crate::shutdown::is_shutting_down;
+        // TODO: Function code was removed as part of https://github.com/ZcashFoundation/zebra/issues/8180
-
+        // Find the removed code at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-chain/src/work/equihash.rs#L115-L166
-        let mut input = Vec::new();
+        // Restore the code when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
-        header
-            .zcash_serialize(&mut input)
-            .expect("serialization into a vec can't fail");
-        // Take the part of the header before the nonce and solution.
-        // This data is kept constant for this solver run.
-        let input = &input[0..Solution::INPUT_LENGTH];
-
-        while !is_shutting_down() {
-            // Don't run the solver if we'd just cancel it anyway.
-            cancel_fn()?;
-
-            let solutions = equihash_solver::tromp::solve_200_9_compressed(input, || {
-                // Cancel the solver if we have a new template.
-                if cancel_fn().is_err() {
-                    return None;
-                }
-
-                // This skips the first nonce, which doesn't matter in practice.
-                Self::next_nonce(&mut header.nonce);
-                Some(*header.nonce)
-            });
-
-            let mut valid_solutions = Vec::new();
-
-            // If we got any solutions, try submitting them, because the new template might just
-            // contain some extra transactions. Mining extra transactions is optional.
-            for solution in &solutions {
-                header.solution = Self::from_bytes(solution)
-                    .expect("unexpected invalid solution: incorrect length");
-
-                // TODO: work out why we sometimes get invalid solutions here
-                if let Err(error) = header.solution.check(&header) {
-                    info!(?error, "found invalid solution for header");
-                    continue;
-                }
-
-                if Self::difficulty_is_valid(&header) {
-                    valid_solutions.push(header);
-                }
-            }
-
-            match valid_solutions.try_into() {
-                Ok(at_least_one_solution) => return Ok(at_least_one_solution),
-                Err(_is_empty_error) => debug!(
-                    solutions = ?solutions.len(),
-                    "found valid solutions which did not pass the validity or difficulty checks"
-                ),
-            }
-        }
 
         Err(SolverCancelled)
     }
 
-    /// Modifies `nonce` to be the next integer in big-endian order.
+    // TODO: Some methods were removed as part of https://github.com/ZcashFoundation/zebra/issues/8180
-    /// Wraps to zero if the next nonce would overflow.
+    // Find the removed code at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-chain/src/work/equihash.rs#L171-L196
-    #[cfg(feature = "internal-miner")]
+    // Restore the code when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
-    fn next_nonce(nonce: &mut [u8; 32]) {
-        let _ignore_overflow = crate::primitives::byte_array::increment_big_endian(&mut nonce[..]);
-    }
-
-    /// Returns `true` if the `nonce` and `solution` in `header` meet the difficulty threshold.
-    ///
-    /// Assumes that the difficulty threshold in the header is valid.
-    #[cfg(feature = "internal-miner")]
-    fn difficulty_is_valid(header: &Header) -> bool {
-        // Simplified from zebra_consensus::block::check::difficulty_is_valid().
-        let difficulty_threshold = header
-            .difficulty_threshold
-            .to_expanded()
-            .expect("unexpected invalid header template: invalid difficulty threshold");
-
-        // TODO: avoid calculating this hash multiple times
-        let hash = header.hash();
-
-        // Note: this comparison is a u256 integer comparison, like zcashd and bitcoin. Greater
-        // values represent *less* work.
-        hash <= difficulty_threshold
-    }
 }
 
 impl PartialEq<Solution> for Solution {

zebra-rpc/src/config/mining.rs

@@ -15,28 +15,9 @@ pub struct Config {
     /// `getblocktemplate` RPC coinbase transaction.
     pub miner_address: Option<transparent::Address>,
 
-    /// Mine blocks using Zebra's internal miner, without an external mining pool or equihash solver.
+    // TODO: Internal miner config code was removed as part of https://github.com/ZcashFoundation/zebra/issues/8180
-    ///
+    // Find the removed code at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-rpc/src/config/mining.rs#L18-L38
-    /// This experimental feature is only supported on testnet.
+    // Restore the code when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
-    /// Mainnet miners should use a mining pool with GPUs or ASICs designed for efficient mining.
-    ///
-    /// The internal miner is off by default.
-    #[cfg(feature = "internal-miner")]
-    pub internal_miner: bool,
-
-    /// The number of internal miner threads used by Zebra.
-    /// These threads are scheduled at low priority.
-    ///
-    /// The number of threads is limited by the available parallelism reported by the OS.
-    /// If the number of threads isn't configured, or can't be detected, Zebra uses one thread.
-    /// This is different from Zebra's other parallelism configs, because mining runs constantly and
-    /// uses a large amount of memory. (144 MB of RAM and 100% of a core per thread.)
-    ///
-    /// If the number of threads is set to zero, Zebra disables mining.
-    /// This matches `zcashd`'s behaviour, but is different from Zebra's other parallelism configs.
-    #[cfg(feature = "internal-miner")]
-    pub internal_miner_threads: usize,
-
     /// Extra data to include in coinbase transaction inputs.
     /// Limited to around 95 bytes by the consensus rules.
     ///
@@ -58,12 +39,9 @@ impl Default for Config {
             // TODO: do we want to default to v5 transactions and Zebra coinbase data?
             extra_coinbase_data: None,
             debug_like_zcashd: true,
-            // TODO: ignore and warn rather than panicking if these fields are in the config,
+            // TODO: Internal miner config code was removed as part of https://github.com/ZcashFoundation/zebra/issues/8180
-            //       but the feature isn't enabled.
+            // Find the removed code at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-rpc/src/config/mining.rs#L61-L66
-            #[cfg(feature = "internal-miner")]
+            // Restore the code when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
-            internal_miner: false,
-            #[cfg(feature = "internal-miner")]
-            internal_miner_threads: 1,
         }
     }
 }
@@ -80,6 +58,9 @@ impl Config {
     /// Is the internal miner enabled using at least one thread?
     #[cfg(feature = "internal-miner")]
     pub fn is_internal_miner_enabled(&self) -> bool {
-        self.internal_miner && self.internal_miner_threads > 0
+        // TODO: Changed to return always false so internal miner is never started. Part of https://github.com/ZcashFoundation/zebra/issues/8180
+        // Find the removed code at https://github.com/ZcashFoundation/zebra/blob/v1.5.1/zebra-rpc/src/config/mining.rs#L83
+        // Restore the code when conditions are met. https://github.com/ZcashFoundation/zebra/issues/8183
+        false
     }
 }

zebra-rpc/src/methods/tests/snapshot/get_block_template_rpcs.rs

@@ -97,8 +97,8 @@ pub async fn test_responses<State, ReadState>(
         miner_address: Some(transparent::Address::from_script_hash(network, [0xad; 20])),
         extra_coinbase_data: None,
         debug_like_zcashd: true,
-        // Use default field values when optional features are enabled in tests
+        // TODO: Use default field values when optional features are enabled in tests #8183
-        ..Default::default()
+        //..Default::default()
     };
 
     // nu5 block height

zebra-rpc/src/methods/tests/vectors.rs

@@ -1236,8 +1236,8 @@ async fn rpc_getblocktemplate_mining_address(use_p2pkh: bool) {
         miner_address,
         extra_coinbase_data: None,
         debug_like_zcashd: true,
-        // Use default field values when optional features are enabled in tests
+        // TODO: Use default field values when optional features are enabled in tests #8183
-        ..Default::default()
+        //..Default::default()
     };
 
     // nu5 block height
@@ -1685,8 +1685,8 @@ async fn rpc_getdifficulty() {
         miner_address: None,
         extra_coinbase_data: None,
         debug_like_zcashd: true,
-        // Use default field values when optional features are enabled in tests
+        // TODO: Use default field values when optional features are enabled in tests #8183
-        ..Default::default()
+        //..Default::default()
     };
 
     // nu5 block height

zebrad/src/components/miner.rs

@@ -106,7 +106,7 @@ where
 ///
 /// See [`run_mining_solver()`] for more details.
 pub async fn init<Mempool, State, Tip, BlockVerifierRouter, SyncStatus, AddressBook>(
-    config: Config,
+    _config: Config,
     rpc: GetBlockTemplateRpcImpl<Mempool, State, Tip, BlockVerifierRouter, SyncStatus, AddressBook>,
 ) -> Result<(), Report>
 where
@@ -138,7 +138,9 @@ where
     SyncStatus: ChainSyncStatus + Clone + Send + Sync + 'static,
     AddressBook: AddressBookPeers + Clone + Send + Sync + 'static,
 {
-    let configured_threads = config.internal_miner_threads;
+    // TODO: change this to `config.internal_miner_threads` when internal miner feature is added back.
+    //       https://github.com/ZcashFoundation/zebra/issues/8183
+    let configured_threads = 1;
     // If we can't detect the number of cores, use the configured number.
     let available_threads = available_parallelism()
         .map(usize::from)