feat(l1): bal prometheus instruments, dashboard panels, and localnet fixture

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Ethrex Changelog
 
+## Observability
+
+### 2026-05-27
+
+- Add BAL (EIP-7928) Prometheus instruments (`bal_blocks_total`, `bal_size_bytes`, `bal_size_bytes_histogram`, `bal_account_count`, `bal_slot_count`) and a BAL row in the `ethrex_l1_perf` Grafana dashboard [#6678](https://github.com/lambdaclass/ethrex/pull/6678)
+
 ## Perf
 
 ### 2026-05-19

crates/blockchain/blockchain.rs

@@ -110,6 +110,8 @@ use tokio_util::sync::CancellationToken;
 
 use vm::StoreVmDatabase;
 
+#[cfg(feature = "metrics")]
+use ethrex_metrics::bal::METRICS_BAL;
 #[cfg(feature = "metrics")]
 use ethrex_metrics::blocks::METRICS_BLOCKS;
 
@@ -1980,6 +1982,17 @@ impl Blockchain {
             );
         }
 
+        metrics!(if let Some(bal_ref) = produced_bal.as_ref().or(bal) {
+            let account_count = bal_ref.accounts().len() as u64;
+            let slot_count = bal_ref.item_count().saturating_sub(account_count);
+            let size_bytes = bal_ref.length() as f64;
+            METRICS_BAL.blocks_total.inc();
+            METRICS_BAL.size_bytes.set(size_bytes);
+            METRICS_BAL.size_bytes_histogram.observe(size_bytes);
+            METRICS_BAL.account_count.set(account_count as i64);
+            METRICS_BAL.slot_count.set(slot_count as i64);
+        });
+
         Ok((produced_bal, result))
     }
 

crates/blockchain/metrics/bal.rs

@@ -0,0 +1,76 @@
+use prometheus::{
+    Gauge, Histogram, IntCounter, IntGauge, register_gauge, register_histogram,
+    register_int_counter, register_int_gauge,
+};
+use std::sync::LazyLock;
+
+// Metrics defined in this module register into the Prometheus default registry.
+// The metrics API exposes them via `gather_default_metrics()`.
+
+pub static METRICS_BAL: LazyLock<MetricsBal> = LazyLock::new(MetricsBal::default);
+
+// Histogram bucket layout for RLP-encoded BAL sizes: 1 KiB base, doubling, 16
+// buckets -> 1 KiB, 2 KiB, 4 KiB, ..., 32 MiB. Observed sizes are always >= 1
+// byte (the smallest BAL RLP-encodes to a non-empty list), so there is no zero
+// floor bucket.
+const BAL_SIZE_BUCKET_START_BYTES: f64 = 1024.0;
+const BAL_SIZE_BUCKET_FACTOR: f64 = 2.0;
+const BAL_SIZE_BUCKET_COUNT: usize = 16;
+
+#[derive(Debug, Clone)]
+pub struct MetricsBal {
+    /// Cumulative count of BAL-carrying blocks processed (post-Amsterdam).
+    pub blocks_total: IntCounter,
+    /// RLP-encoded size of the most recent BAL, in bytes (per-block snapshot).
+    pub size_bytes: Gauge,
+    /// Distribution of RLP-encoded BAL sizes in bytes.
+    pub size_bytes_histogram: Histogram,
+    /// Number of accounts in the most recent BAL (per-block snapshot).
+    pub account_count: IntGauge,
+    /// Unique storage slots (writes + reads) in the most recent BAL (per-block snapshot).
+    pub slot_count: IntGauge,
+}
+
+impl Default for MetricsBal {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl MetricsBal {
+    pub fn new() -> Self {
+        MetricsBal {
+            blocks_total: register_int_counter!(
+                "bal_blocks_total",
+                "Cumulative count of Block Access List (EIP-7928) carrying blocks processed"
+            )
+            .expect("Failed to create bal_blocks_total metric"),
+            size_bytes: register_gauge!(
+                "bal_size_bytes",
+                "RLP-encoded size of the most recent Block Access List, in bytes"
+            )
+            .expect("Failed to create bal_size_bytes metric"),
+            size_bytes_histogram: register_histogram!(
+                "bal_size_bytes_histogram",
+                "Distribution of RLP-encoded Block Access List sizes in bytes",
+                prometheus::exponential_buckets(
+                    BAL_SIZE_BUCKET_START_BYTES,
+                    BAL_SIZE_BUCKET_FACTOR,
+                    BAL_SIZE_BUCKET_COUNT,
+                )
+                .expect("Invalid BAL histogram bucket params")
+            )
+            .expect("Failed to create bal_size_bytes_histogram metric"),
+            account_count: register_int_gauge!(
+                "bal_account_count",
+                "Number of accounts in the most recent Block Access List"
+            )
+            .expect("Failed to create bal_account_count metric"),
+            slot_count: register_int_gauge!(
+                "bal_slot_count",
+                "Unique storage slots (writes + reads) in the most recent BAL"
+            )
+            .expect("Failed to create bal_slot_count metric"),
+        }
+    }
+}

crates/blockchain/metrics/mod.rs

@@ -1,6 +1,8 @@
 #[cfg(feature = "api")]
 pub mod api;
 #[cfg(any(feature = "api", feature = "metrics"))]
+pub mod bal;
+#[cfg(any(feature = "api", feature = "metrics"))]
 pub mod blocks;
 #[cfg(feature = "api")]
 pub mod l2;