Enable skipping blob pruning at each epoch

beacon_node/src/cli.rs

@@ -555,10 +555,19 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
             Arg::with_name("prune-blobs")
                 .long("prune-blobs")
                 .help("Prune blobs from Lighthouse's database when they are older than the data \
-                       data availability boundary relative to the current head.")
+                       data availability boundary relative to the current epoch.")
                 .takes_value(true)
                 .default_value("true")
         )
+        .arg(
+            Arg::with_name("epochs-per-blob-prune")
+                .long("epochs-per-blob-prune")
+                .help("The epoch interval with which to prune blobs from Lighthouse's \
+                       database when they are older than the data data availability \
+                       boundary relative to the current epoch.")
+                .takes_value(true)
+                .default_value("1")
+        )
 
         /*
          * Misc.

beacon_node/src/config.rs

@@ -415,6 +415,12 @@ pub fn get_config<E: EthSpec>(
         client_config.store.prune_blobs = prune_blobs;
     }
 
+    if let Some(epochs_per_blob_prune) =
+        clap_utils::parse_optional(cli_args, "epochs-per-blob-prune")?
+    {
+        client_config.store.epochs_per_blob_prune = epochs_per_blob_prune;
+    }
+
     /*
      * Zero-ports
      *

beacon_node/store/src/config.rs

@@ -8,6 +8,7 @@ pub const PREV_DEFAULT_SLOTS_PER_RESTORE_POINT: u64 = 2048;
 pub const DEFAULT_SLOTS_PER_RESTORE_POINT: u64 = 8192;
 pub const DEFAULT_BLOCK_CACHE_SIZE: usize = 5;
 pub const DEFAULT_BLOB_CACHE_SIZE: usize = 5;
+pub const DEFAULT_EPOCHS_PER_BLOB_PRUNE: u64 = 1;
 
 /// Database configuration parameters.
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
@@ -28,6 +29,8 @@ pub struct StoreConfig {
     pub prune_payloads: bool,
     /// Whether to prune blobs older than the blob data availability boundary.
     pub prune_blobs: bool,
+    /// Frequency of blob pruning. Default: every epoch.
+    pub epochs_per_blob_prune: u64,
 }
 
 /// Variant of `StoreConfig` that gets written to disk. Contains immutable configuration params.
@@ -53,6 +56,7 @@ impl Default for StoreConfig {
             compact_on_prune: true,
             prune_payloads: true,
             prune_blobs: true,
+            epochs_per_blob_prune: DEFAULT_EPOCHS_PER_BLOB_PRUNE,
         }
     }
 }

beacon_node/store/src/hot_cold_store.rs

@@ -1721,10 +1721,14 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
             }
         };
 
-        if blob_info.last_pruned_epoch == blob_info.next_epoch_to_prune && !force {
+        if !force {
+            let epochs_per_blob_prune =
+                Epoch::new(self.get_config().epochs_per_blob_prune * E::slots_per_epoch());
+            if blob_info.last_pruned_epoch + epochs_per_blob_prune > blob_info.next_epoch_to_prune {
                 info!(self.log, "Blobs sidecars are pruned");
                 return Ok(());
             }
+        }
 
         let dab_state_root = blob_info.data_availability_boundary.state_root;
 
@@ -1840,7 +1844,7 @@ pub fn migrate_database<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>>(
     }
 
     // Prune blobs before migration.
-    store.try_prune_blobs(false)?;
+    store.try_prune_blobs(true)?;
 
     let mut hot_db_ops: Vec<StoreOp<E>> = Vec::new();