From 5de30139aef6d0b6aae4a609d8b80c2a528e407d Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Tue, 16 Feb 2016 01:23:07 -0800
Subject: [PATCH] lru. misc.

---
 lib/bcoin/blockdb.js |  3 ---
 lib/bcoin/hd.js      |  8 ++++++--
 lib/bcoin/lru.js     | 40 ++++++++++++++++++++++++++--------------
 3 files changed, 32 insertions(+), 19 deletions(-)

diff --git a/lib/bcoin/blockdb.js b/lib/bcoin/blockdb.js
index 4dde2840..636a5992 100644
--- a/lib/bcoin/blockdb.js
+++ b/lib/bcoin/blockdb.js
@@ -52,9 +52,6 @@ function BlockDB(options) {
     compression: true,
     cacheSize: 16 * 1024 * 1024,
     writeBufferSize: 8 * 1024 * 1024,
-    // https://leveldb.googlecode.com/git-history/master/doc/index.html
-    // Higher block size = better for iterators
-    // Lower block size = better for gets
     // blockSize: 4 * 1024,
     maxOpenFiles: 8192,
     // blockRestartInterval: 16,
diff --git a/lib/bcoin/hd.js b/lib/bcoin/hd.js
index 080f616f..6bf3a1fe 100644
--- a/lib/bcoin/hd.js
+++ b/lib/bcoin/hd.js
@@ -1212,10 +1212,10 @@ function pbkdf2(key, salt, iterations, dkLen) {
     throw new TypeError('salt must a string or array');
 
   if (typeof key === 'string')
-    key = utils.toArray(key, null);
+    key = new Buffer(key, 'ascii');
 
   if (typeof salt === 'string')
-    salt = utils.toArray(salt, null);
+    salt = new Buffer(salt, 'ascii');
 
   var DK = new Buffer(dkLen);
   var U = new Buffer(hLen);
@@ -1254,6 +1254,10 @@ function pbkdf2(key, salt, iterations, dkLen) {
   return DK;
 }
 
+HD.cache = new bcoin.lru(500, function(key, value) {
+  return 1;
+});
+
 var cache = {
   data: {},
   count: 0
diff --git a/lib/bcoin/lru.js b/lib/bcoin/lru.js
index 5117aece..dd37ec52 100644
--- a/lib/bcoin/lru.js
+++ b/lib/bcoin/lru.js
@@ -29,7 +29,7 @@ LRU.prototype._getSize = function _getSize(item) {
   var keySize = item.key.length * 2;
 
   if (this.getSize)
-    return keySize + this.getSize(item.value);
+    return this.getSize(item.key, item.value);
 
   if (item.value == null)
     return keySize + 1;
@@ -56,16 +56,29 @@ LRU.prototype._getSize = function _getSize(item) {
 };
 
 LRU.prototype._compact = function _compact() {
-  var item;
+  var item, next;
 
   if (this.size <= this.maxSize)
     return;
 
-  for (item = this.head; item; item = item.next) {
-    if (this.size < this.maxSize)
+  for (item = this.head; item; item = next) {
+    if (this.size <= this.maxSize)
       break;
-    this.remove(item.key);
+    this.size -= this._getSize(item);
+    delete this.data[item.key];
+    next = item.next;
+    item.prev = null;
+    item.next = null;
   }
+
+  if (!item) {
+    this.head = null;
+    this.tail = null;
+    return;
+  }
+
+  this.head = item;
+  item.prev = null;
 };
 
 LRU.prototype.set = function set(key, value) {
@@ -201,16 +214,16 @@ var a3 = '3';
 var a4 = '4';
 var a5 = '5';
 var a6 = '6';
-var lru = new LRU(((2 * 4) + 4) * 2);
+var lru = new LRU(4, function() { return 1; });
 lru.set('a1', a1);
 assert(lru.get('a1') === '1');
-assert(lru.size === ((2 * 1) + 1) * 2);
+assert(lru.size === 1);
 assert(lru.head.key === 'a1' && lru.tail.key === 'a1' && !lru.head.prev && !lru.head.next);
 lru._keys();
 // console.log(lru._keys());
 lru.set('a2', a2);
 assert(lru.get('a2') === '2');
-assert(lru.size === ((2 * 2) + 2) * 2);
+assert(lru.size === 2);
 assert(lru.head.key === 'a1' && lru.tail.key === 'a2'
   && !lru.head.prev && lru.head.next.key === 'a2'
   && !lru.tail.next && lru.tail.prev.key === 'a1');
@@ -218,17 +231,17 @@ lru._keys();
 // console.log(lru._keys());
 lru.set('a3', a3);
 assert(lru.get('a3') === '3');
-assert(lru.size === ((2 * 3) + 3) * 2);
+assert(lru.size === 3);
 lru._keys();
 // console.log(lru._keys());
 lru.set('a3', a3);
 assert(lru.get('a3') === '3');
-assert(lru.size === ((2 * 3) + 3) * 2);
+assert(lru.size === 3);
 lru._keys();
 // console.log(lru._keys());
 lru.set('a4', a4);
 assert(lru.get('a4') === '4');
-assert(lru.size === ((2 * 4) + 4) * 2);
+assert(lru.size === 4);
 lru._keys();
 // console.log(lru._keys());
 assert(lru.get('a1'));
@@ -243,16 +256,15 @@ assert(lru.head.key === 'a2' && lru.tail.key === 'a4'
   && !lru.tail.next && lru.tail.prev.key === 'a3');
 lru.set('a5', a5);
 assert(lru.get('a5') === '5');
-assert(lru.size === ((2 * 4) + 4) * 2);
+assert(lru.size === 4);
 assert(!lru.get('a1'));
 lru._keys();
 // console.log(lru._keys());
 lru.get('a2');
 lru._keys();
-// console.log(lru._keys());
 lru.set('a6', a6);
 assert(lru.get('a6') === '6');
-assert(lru.size === ((2 * 4) + 4) * 2);
+assert(lru.size === 4);
 assert(!lru.get('a3'));
 lru._keys();
 // console.log(lru._keys());