network: add block batch size.

lib/bcoin/network.js

@@ -55,6 +55,7 @@ function Network(options) {
   this.maxRate = options.maxRate;
   this.selfConnect = options.selfConnect;
   this.requestMempool = options.requestMempool;
+  this.batchSize = options.batchSize;
 }
 
 /**
@@ -127,6 +128,26 @@ Network.prototype.getRate = function getRate() {
   return Math.min(this.feeRate, this.maxRate);
 };
 
+/**
+ * Determine how many blocks to request
+ * based on current height of the chain.
+ * @param {Number} height
+ * @returns {Number}
+ */
+
+Network.prototype.getBatchSize = function getBatchSize(height) {
+  var batch = this.batchSize;
+  var last = batch.length - 1;
+  var i;
+
+  for (i = 0; i < last; i++) {
+    if (height <= batch[i][0])
+      return batch[i][1];
+  }
+
+  return batch[last][0];
+};
+
 /**
  * Create a network. Get existing network if possible.
  * @param {NetworkType|Object} options

lib/bcoin/pool.js

@@ -1600,17 +1600,7 @@ Pool.prototype._sendRequests = function _sendRequests(peer) {
     items = peer.queue.block.slice();
     peer.queue.block.length = 0;
   } else {
-    // Blocks start getting big after 150k.
-    if (this.chain.height <= 100000)
-      size = 500;
-    else if (this.chain.height <= 150000)
-      size = 250;
-    else if (this.chain.height <= 250000)
-      size = 150;
-    else if (this.chain.height <= 350000)
-      size = 50;
-    else
-      size = 20;
+    size = this.network.getBatchSize(this.chain.height);
 
     if (this.request.activeBlocks >= size)
       return;

lib/bcoin/protocol/network.js

@@ -444,6 +444,19 @@ main.selfConnect = false;
 
 main.requestMempool = false;
 
+/**
+ * Number of blocks to request based on chain height.
+ * @const {Array}
+ */
+
+main.batchSize = [
+  [100000, 500],
+  [150000, 250],
+  [250000, 150],
+  [350000, 50],
+  [20]
+];
+
 /*
  * Testnet (v3)
  * https://en.bitcoin.it/wiki/Testnet
@@ -591,6 +604,11 @@ testnet.selfConnect = false;
 
 testnet.requestMempool = true;
 
+testnet.batchSize = [
+  [100000, 500],
+  [250]
+];
+
 /*
  * Regtest
  */
@@ -731,6 +749,10 @@ regtest.selfConnect = false;
 
 regtest.requestMempool = true;
 
+regtest.batchSize = [
+  [500]
+];
+
 /*
  * segnet3
  */
@@ -850,6 +872,11 @@ segnet3.selfConnect = false;
 
 segnet3.requestMempool = true;
 
+segnet3.batchSize = [
+  [20000, 500],
+  [250]
+];
+
 /*
  * segnet4
  */
@@ -983,3 +1010,8 @@ segnet4.maxRate = 40000;
 segnet4.selfConnect = false;
 
 segnet4.requestMempool = true;
+
+segnet4.batchSize = [
+  [17000, 500],
+  [250]
+];