Switch default slasher backend to LMDB

Makefile

@@ -145,8 +145,9 @@ test-op-pool-%:
 
 # Run the tests in the `slasher` crate for all supported database backends.
 test-slasher:
-	cargo test --release -p slasher --features mdbx
-	cargo test --release -p slasher --no-default-features --features lmdb
+	cargo test --release -p slasher --features lmdb
+	cargo test --release -p slasher --no-default-features --features mdbx
+	cargo test --release -p slasher --features lmdb,mdbx # both backends enabled
 
 # Runs only the tests/state_transition_vectors tests.
 run-state-transition-tests:

beacon_node/Cargo.toml

@@ -36,7 +36,7 @@ clap_utils = { path = "../common/clap_utils" }
 hyper = "0.14.4"
 lighthouse_version = { path = "../common/lighthouse_version" }
 hex = "0.4.2"
-slasher = { path = "../slasher", default-features = false }
+slasher = { path = "../slasher" }
 monitoring_api = { path = "../common/monitoring_api" }
 sensitive_url = { path = "../common/sensitive_url" }
 http_api = { path = "http_api" }

beacon_node/beacon_chain/Cargo.toml

@@ -54,7 +54,7 @@ fork_choice = { path = "../../consensus/fork_choice" }
 task_executor = { path = "../../common/task_executor" }
 derivative = "2.1.1"
 itertools = "0.10.0"
-slasher = { path = "../../slasher", default-features = false }
+slasher = { path = "../../slasher" }
 eth2 = { path = "../../common/eth2" }
 strum = { version = "0.24.0", features = ["derive"] }
 logging = { path = "../../common/logging" }

beacon_node/client/Cargo.toml

@@ -39,7 +39,7 @@ time = "0.3.5"
 directory = {path = "../../common/directory"}
 http_api = { path = "../http_api" }
 http_metrics = { path = "../http_metrics" }
-slasher = { path = "../../slasher", default-features = false }
+slasher = { path = "../../slasher" }
 slasher_service = { path = "../../slasher/service" }
 monitoring_api = {path = "../../common/monitoring_api"}
 execution_layer = { path = "../execution_layer" }

beacon_node/src/lib.rs

@@ -16,7 +16,7 @@ pub use client::{Client, ClientBuilder, ClientConfig, ClientGenesis};
 pub use config::{get_config, get_data_dir, get_slots_per_restore_point, set_network_config};
 use environment::RuntimeContext;
 pub use eth2_config::Eth2Config;
-use slasher::Slasher;
+use slasher::{DatabaseBackendOverride, Slasher};
 use slog::{info, warn};
 use std::ops::{Deref, DerefMut};
 use std::sync::Arc;
@@ -86,7 +86,27 @@ impl<E: EthSpec> ProductionBeaconNode<E> {
             .http_api_config(client_config.http_api.clone())
             .disk_store(&db_path, &freezer_db_path, store_config, log.clone())?;
 
-        let builder = if let Some(slasher_config) = client_config.slasher.clone() {
+        let builder = if let Some(mut slasher_config) = client_config.slasher.clone() {
+            match slasher_config.override_backend() {
+                DatabaseBackendOverride::Success(old_backend) => {
+                    info!(
+                        log,
+                        "Slasher backend overriden";
+                        "reason" => "database exists",
+                        "configured_backend" => %old_backend,
+                        "override_backend" => %slasher_config.backend,
+                    );
+                }
+                DatabaseBackendOverride::Failure(path) => {
+                    warn!(
+                        log,
+                        "Slasher backend override failed";
+                        "advice" => "delete old MDBX database or enable MDBX backend",
+                        "path" => path.display()
+                    );
+                }
+                _ => {}
+            }
             let slasher = Arc::new(
                 Slasher::open(slasher_config, log.new(slog::o!("service" => "slasher")))
                     .map_err(|e| format!("Slasher open error: {:?}", e))?,

beacon_node/store/Cargo.toml

@@ -10,7 +10,7 @@ beacon_chain = {path = "../beacon_chain"}
 
 [dependencies]
 db-key = "0.0.5"
-leveldb = { version = "0.8.6", default-features = false }
+leveldb = { version = "0.8.6" }
 parking_lot = "0.12.0"
 itertools = "0.10.0"
 ethereum_ssz = "0.5.0"

book/src/installation-source.md

@@ -5,7 +5,7 @@ the instructions below, and then proceed to [Building Lighthouse](#build-lightho
 
 ## Dependencies
 
-First, **install Rust** using [rustup](https://rustup.rs/)： 
+First, **install Rust** using [rustup](https://rustup.rs/)：
 
 ```bash
 curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
@@ -64,10 +64,10 @@ After this, you are ready to [build Lighthouse](#build-lighthouse).
 
 1. Install [Git](https://git-scm.com/download/win).
 1. Install the [Chocolatey](https://chocolatey.org/install) package manager for Windows.
-    > Tips: 
+    > Tips:
     > - Use PowerShell to install. In Windows, search for PowerShell and run as administrator.
     > - You must ensure `Get-ExecutionPolicy` is not Restricted. To test this, run `Get-ExecutionPolicy` in PowerShell. If it returns `restricted`, then run `Set-ExecutionPolicy AllSigned`, and then run
-    ```bash 
+    ```bash
     Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))
     ```
     > - To verify that Chocolatey is ready, run `choco` and it should return the version.
@@ -159,13 +159,13 @@ Commonly used features include:
 * `gnosis`: support for the Gnosis Beacon Chain.
 * `portable`: support for legacy hardware.
 * `modern`: support for exclusively modern hardware.
-* `slasher-mdbx`: support for the MDBX slasher backend. Enabled by default.
-* `slasher-lmdb`: support for the LMDB slasher backend.
+* `slasher-lmdb`: support for the LMDB slasher backend. Enabled by default.
+* `slasher-mdbx`: support for the MDBX slasher backend.
 * `jemalloc`: use [`jemalloc`][jemalloc] to allocate memory. Enabled by default on Linux and macOS.
   Not supported on Windows.
 * `spec-minimal`: support for the minimal preset (useful for testing).
 
-Default features (e.g. `slasher-mdbx`) may be opted out of using the `--no-default-features`
+Default features (e.g. `slasher-lmdb`) may be opted out of using the `--no-default-features`
 argument for `cargo`, which can be plumbed in via the `CARGO_INSTALL_EXTRA_FLAGS` environment variable.
 E.g.
 

book/src/slasher.md

@@ -47,23 +47,49 @@ directory.
 
 * Flag: `--slasher-backend NAME`
 * Argument: one of `mdbx`, `lmdb` or `disabled`
-* Default: `mdbx`
+* Default: `lmdb` for new installs, `mdbx` if an MDBX database already exists
 
-Since Lighthouse v2.6.0 it is possible to use one of several database backends with the slasher:
+It is possible to use one of several database backends with the slasher:
 
-- MDBX (default)
-- LMDB
+- LMDB (default)
+- MDBX
 
 The advantage of MDBX is that it performs compaction, resulting in less disk usage over time. The
-disadvantage is that upstream MDBX has removed support for Windows and macOS, so Lighthouse is stuck
-on an older version. If bugs are found in our pinned version of MDBX it may be deprecated in future.
+disadvantage is that upstream MDBX is unstable, so Lighthouse is pinned to a specific version.
+If bugs are found in our pinned version of MDBX it may be deprecated in future.
 
-LMDB does not have compaction but is more stable upstream than MDBX. It is not currently recommended
-to use the LMDB backend on Windows.
+LMDB does not have compaction but is more stable upstream than MDBX. If running with the LMDB
+backend on Windows it is recommended to allow extra space due to this issue:
+[sigp/lighthouse#2342](https://github.com/sigp/lighthouse/issues/2342).
 
 More backends may be added in future.
 
-### Switching Backends
+#### Backend Override
+
+The default backend was changed from MDBX to LMDB in Lighthouse v4.3.0.
+
+If an MDBX database is already found on disk, then Lighthouse will try to use it. This will result
+in a log at start-up:
+
+```
+INFO Slasher backend overriden    reason: database exists, configured_backend: lmdb, overriden_backend: mdbx
+```
+
+If the running Lighthouse binary doesn't have the MDBX backend enabled but an existing database is
+found, then a warning will be logged and Lighthouse will continue using the LMDB backend:
+
+```
+WARN Slasher backend override failed    advice: delete old MDBX database or enable MDBX backend, path: /home/user/.lighthouse/mainnet/beacon/slasher_db/mdbx.dat
+```
+
+In this case you should either obtain a Lighthouse binary with the MDBX backend enabled, or delete
+the files for the old backend. The pre-built Lighthouse binaries and Docker images have MDBX enabled,
+or if you're [building from source](./installation-source.md) you can enable the `slasher-mdbx` feature.
+
+To delete the files, use the `path` from the `WARN` log, and then delete the `mbdx.dat` and
+`mdbx.lck` files.
+
+#### Switching Backends
 
 If you change database backends and want to reclaim the space used by the old backend you can
 delete the following files from your `slasher_db` directory:

lighthouse/Cargo.toml

@@ -7,7 +7,7 @@ autotests = false
 rust-version = "1.68.2"
 
 [features]
-default = ["slasher-mdbx"]
+default = ["slasher-lmdb"]
 # Writes debugging .ssz files to /tmp during block processing.
 write_ssz_files = ["beacon_node/write_ssz_files"]
 # Compiles the BLS crypto code so that the binary is portable across machines.
@@ -55,7 +55,7 @@ malloc_utils = { path = "../common/malloc_utils" }
 directory = { path = "../common/directory" }
 unused_port = { path = "../common/unused_port" }
 database_manager = { path = "../database_manager" }
-slasher = { path = "../slasher", default-features = false }
+slasher = { path = "../slasher" }
 
 [dev-dependencies]
 tempfile = "3.1.0"

lighthouse/tests/beacon_node.rs

@@ -1903,7 +1903,7 @@ fn slasher_backend_default() {
         .run_with_zero_port()
         .with_config(|config| {
             let slasher_config = config.slasher.as_ref().unwrap();
-            assert_eq!(slasher_config.backend, slasher::DatabaseBackend::Mdbx);
+            assert_eq!(slasher_config.backend, slasher::DatabaseBackend::Lmdb);
         });
 }
 
@@ -1913,11 +1913,11 @@ fn slasher_backend_override_to_default() {
     // called "disabled" results in a panic.
     CommandLineTest::new()
         .flag("slasher", None)
-        .flag("slasher-backend", Some("mdbx"))
+        .flag("slasher-backend", Some("lmdb"))
         .run_with_zero_port()
         .with_config(|config| {
             let slasher_config = config.slasher.as_ref().unwrap();
-            assert_eq!(slasher_config.backend, slasher::DatabaseBackend::Mdbx);
+            assert_eq!(slasher_config.backend, slasher::DatabaseBackend::Lmdb);
         });
 }
 

slasher/Cargo.toml

@@ -5,7 +5,7 @@ authors = ["Michael Sproul <[email protected]>"]
 edition = "2021"
 
 [features]
-default = ["mdbx"]
+default = ["lmdb"]
 mdbx = ["dep:mdbx"]
 lmdb = ["lmdb-rkv", "lmdb-rkv-sys"]
 

slasher/service/Cargo.toml

@@ -9,7 +9,7 @@ beacon_chain = { path = "../../beacon_node/beacon_chain" }
 directory = { path = "../../common/directory" }
 lighthouse_network = { path = "../../beacon_node/lighthouse_network" }
 network = { path = "../../beacon_node/network" }
-slasher = { path = "..", default-features = false }
+slasher = { path = ".." }
 slog = "2.5.2"
 slot_clock = { path = "../../common/slot_clock" }
 state_processing = { path = "../../consensus/state_processing" }

slasher/src/config.rs

@@ -13,15 +13,16 @@ pub const DEFAULT_MAX_DB_SIZE: usize = 256 * 1024; // 256 GiB
 pub const DEFAULT_ATTESTATION_ROOT_CACHE_SIZE: usize = 100_000;
 pub const DEFAULT_BROADCAST: bool = false;
 
-#[cfg(feature = "mdbx")]
+#[cfg(all(feature = "mdbx", not(feature = "lmdb")))]
 pub const DEFAULT_BACKEND: DatabaseBackend = DatabaseBackend::Mdbx;
-#[cfg(all(feature = "lmdb", not(feature = "mdbx")))]
+#[cfg(feature = "lmdb")]
 pub const DEFAULT_BACKEND: DatabaseBackend = DatabaseBackend::Lmdb;
 #[cfg(not(any(feature = "mdbx", feature = "lmdb")))]
 pub const DEFAULT_BACKEND: DatabaseBackend = DatabaseBackend::Disabled;
 
 pub const MAX_HISTORY_LENGTH: usize = 1 << 16;
 pub const MEGABYTE: usize = 1 << 20;
+pub const MDBX_DATA_FILENAME: &str = "mdbx.dat";
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Config {
@@ -64,6 +65,13 @@ pub enum DatabaseBackend {
     Disabled,
 }
 
+#[derive(Debug, PartialEq)]
+pub enum DatabaseBackendOverride {
+    Success(DatabaseBackend),
+    Failure(PathBuf),
+    Noop,
+}
+
 impl Config {
     pub fn new(database_path: PathBuf) -> Self {
         Self {
@@ -161,4 +169,28 @@ impl Config {
             .filter(move |v| self.validator_chunk_index(**v) == validator_chunk_index)
             .copied()
     }
+
+    pub fn override_backend(&mut self) -> DatabaseBackendOverride {
+        let mdbx_path = self.database_path.join(MDBX_DATA_FILENAME);
+
+        #[cfg(feature = "mdbx")]
+        let already_mdbx = self.backend == DatabaseBackend::Mdbx;
+        #[cfg(not(feature = "mdbx"))]
+        let already_mdbx = false;
+
+        if !already_mdbx && mdbx_path.exists() {
+            #[cfg(feature = "mdbx")]
+            {
+                let old_backend = self.backend;
+                self.backend = DatabaseBackend::Mdbx;
+                DatabaseBackendOverride::Success(old_backend)
+            }
+            #[cfg(not(feature = "mdbx"))]
+            {
+                DatabaseBackendOverride::Failure(mdbx_path)
+            }
+        } else {
+            DatabaseBackendOverride::Noop
+        }
+    }
 }

slasher/src/lib.rs

@@ -21,7 +21,7 @@ pub use crate::slasher::Slasher;
 pub use attestation_queue::{AttestationBatch, AttestationQueue, SimpleBatch};
 pub use attester_record::{AttesterRecord, CompactAttesterRecord, IndexedAttesterRecord};
 pub use block_queue::BlockQueue;
-pub use config::{Config, DatabaseBackend};
+pub use config::{Config, DatabaseBackend, DatabaseBackendOverride};
 pub use database::{
     interface::{Database, Environment, RwTransaction},
     IndexedAttestationId, SlasherDB,

slasher/tests/backend.rs

@@ -0,0 +1,57 @@
+#![cfg(any(feature = "mdbx", feature = "lmdb"))]
+
+use slasher::{config::MDBX_DATA_FILENAME, Config, DatabaseBackend, DatabaseBackendOverride};
+use std::fs::File;
+use tempfile::tempdir;
+
+#[test]
+#[cfg(all(feature = "mdbx", feature = "lmdb"))]
+fn override_no_existing_db() {
+    let tempdir = tempdir().unwrap();
+    let mut config = Config::new(tempdir.path().into());
+    assert_eq!(config.override_backend(), DatabaseBackendOverride::Noop);
+}
+
+#[test]
+#[cfg(all(feature = "mdbx", feature = "lmdb"))]
+fn override_with_existing_mdbx_db() {
+    let tempdir = tempdir().unwrap();
+    let mut config = Config::new(tempdir.path().into());
+
+    File::create(config.database_path.join(MDBX_DATA_FILENAME)).unwrap();
+
+    assert_eq!(
+        config.override_backend(),
+        DatabaseBackendOverride::Success(DatabaseBackend::Lmdb)
+    );
+    assert_eq!(config.backend, DatabaseBackend::Mdbx);
+}
+
+#[test]
+#[cfg(all(feature = "mdbx", feature = "lmdb"))]
+fn no_override_with_existing_mdbx_db() {
+    let tempdir = tempdir().unwrap();
+    let mut config = Config::new(tempdir.path().into());
+    config.backend = DatabaseBackend::Mdbx;
+
+    File::create(config.database_path.join(MDBX_DATA_FILENAME)).unwrap();
+
+    assert_eq!(config.override_backend(), DatabaseBackendOverride::Noop);
+    assert_eq!(config.backend, DatabaseBackend::Mdbx);
+}
+
+#[test]
+#[cfg(all(not(feature = "mdbx"), feature = "lmdb"))]
+fn failed_override_with_existing_mdbx_db() {
+    let tempdir = tempdir().unwrap();
+    let mut config = Config::new(tempdir.path().into());
+
+    let filename = config.database_path.join(MDBX_DATA_FILENAME);
+    File::create(&filename).unwrap();
+
+    assert_eq!(
+        config.override_backend(),
+        DatabaseBackendOverride::Failure(filename)
+    );
+    assert_eq!(config.backend, DatabaseBackend::Lmdb);
+}