Add delete subcommand to ledger-tool bigtable (#19931)

* Add `delete` subcommand to `ledger-tool bigtable` command

* feedback

ledger/src/bigtable_delete.rs

@@ -0,0 +1,53 @@
+use {log::*, solana_measure::measure::Measure, solana_sdk::clock::Slot, std::result::Result};
+
+// Attempt to delete this many blocks in parallel
+const NUM_BLOCKS_TO_DELETE_IN_PARALLEL: usize = 32;
+
+pub async fn delete_confirmed_blocks(
+    bigtable: solana_storage_bigtable::LedgerStorage,
+    blocks_to_delete: Vec<Slot>,
+    dry_run: bool,
+) -> Result<(), Box<dyn std::error::Error>> {
+    let mut measure = Measure::start("entire delete");
+
+    if blocks_to_delete.is_empty() {
+        info!("No blocks to be deleted");
+        return Ok(());
+    }
+    info!("{} blocks to be deleted", blocks_to_delete.len());
+
+    let mut failures = 0;
+    for blocks in blocks_to_delete.chunks(NUM_BLOCKS_TO_DELETE_IN_PARALLEL) {
+        let mut measure_delete = Measure::start("Delete");
+        info!("Preparing the next {} blocks for deletion", blocks.len());
+
+        let deletion_futures = blocks
+            .iter()
+            .map(|block| bigtable.delete_confirmed_block(*block, dry_run));
+
+        for (block, result) in blocks
+            .iter()
+            .zip(futures::future::join_all(deletion_futures).await)
+        {
+            if result.is_err() {
+                error!(
+                    "delete_confirmed_block({}) failed: {:?}",
+                    block,
+                    result.err()
+                );
+                failures += 1;
+            }
+        }
+
+        measure_delete.stop();
+        info!("{} for {} blocks", measure_delete, blocks.len());
+    }
+
+    measure.stop();
+    info!("{}", measure);
+    if failures > 0 {
+        Err(format!("Incomplete deletion, {} operations failed", failures).into())
+    } else {
+        Ok(())
+    }
+}