blockchain: remove blocks after commit

lib/blockchain/chaindb.js

@@ -762,7 +762,6 @@ class ChainDB {
 
     const start = pruneAfter + 1;
     const end = height - keepBlocks;
-    const b = this.db.batch();
 
     for (let i = start; i <= end; i++) {
       const hash = await this.getHash(i);
@@ -780,16 +779,12 @@ class ChainDB {
       const flags = ChainFlags.fromOptions(options);
       assert(flags.prune);
 
-      b.put(layout.O.encode(), flags.toRaw());
-
-      await b.write();
+      await this.db.put(layout.O.encode(), flags.toRaw());
     } catch (e) {
       options.prune = false;
       throw e;
     }
 
-    await this.db.compactRange();
-
     return true;
   }
 
@@ -1466,6 +1461,10 @@ class ChainDB {
 
     await this.commit();
 
+    // Remove undo data _after_ successful commit.
+    if (this.blocks)
+      await this.blocks.pruneUndo(entry.hash);
+
     return view;
   }
 
@@ -1582,6 +1581,12 @@ class ChainDB {
 
       await this.commit();
 
+      // Remove block and undo data _after_ successful commit.
+      if (this.blocks) {
+        await this.blocks.pruneUndo(tip.hash);
+        await this.blocks.prune(tip.hash);
+      }
+
       // Update caches _after_ successful commit.
       this.cacheHeight.remove(tip.height);
       this.cacheHash.remove(tip.hash);
@@ -1605,15 +1610,23 @@ class ChainDB {
     // one giant atomic write!
     this.start();
 
+    let hashes = [];
+
     try {
       for (const tip of tips)
-        await this._removeChain(tip);
+        hashes = hashes.concat(await this._removeChain(tip));
     } catch (e) {
       this.drop();
       throw e;
     }
 
     await this.commit();
+
+    // SPV doesn't store blocks.
+    if (this.blocks) {
+      for (const hash of hashes)
+        await this.blocks.prune(hash);
+    }
   }
 
   /**
@@ -1631,6 +1644,8 @@ class ChainDB {
 
     this.logger.debug('Removing alternate chain: %h.', tip.hash);
 
+    const hashes = [];
+
     for (;;) {
       if (await this.isMainChain(tip))
         break;
@@ -1641,7 +1656,10 @@ class ChainDB {
       this.del(layout.p.encode(tip.hash));
       this.del(layout.h.encode(tip.hash));
       this.del(layout.e.encode(tip.hash));
-      await this.blocks.prune(tip.hash);
+
+      // Queue block to be pruned on
+      // successful write.
+      hashes.push(tip.hash);
 
       // Queue up hash to be removed
       // on successful write.
@@ -1650,6 +1668,8 @@ class ChainDB {
       tip = await this.getPrevious(tip);
       assert(tip);
     }
+
+    return hashes;
   }
 
   /**
@@ -1692,8 +1712,6 @@ class ChainDB {
     if (!block)
       throw new Error('Block not found.');
 
-    await this.blocks.prune(block.hash());
-
     return this.disconnectBlock(entry, block);
   }
 
@@ -1821,9 +1839,6 @@ class ChainDB {
     // Commit new coin state.
     this.saveView(view);
 
-    // Remove undo coins.
-    await this.blocks.pruneUndo(hash);
-
     return view;
   }