From: adrian <>
Date: Wed, 20 Sep 2006 06:59:26 +0000 (+0000)
Subject: Bypass the expensive check to the allocator getStats() when obtaining inuse data
X-Git-Tag: SQUID_3_0_PRE5~63
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9f9e06f3e0e028258a446df3b4f1f7ef2422c302;p=thirdparty%2Fsquid.git

Bypass the expensive check to the allocator getStats() when obtaining inuse data

A lot of busy code calls getStats() to get the inuse values when calculating
queue length (diskthreads) and store memory use for object memory expiry.
This was destroying performance.

The changes implement a "shortcut" to obtain the inuse values for both the
malloc and mempool allocator. getStats() is still expensive for mempools
(as it does GC before updating all the statistics to get accurate information)
but code has been modified to not use getStats() where all it wanted was
inuse info.
---

diff --git a/include/MemPool.h b/include/MemPool.h
index 74dfd595be..c2e97d372f 100644
--- a/include/MemPool.h
+++ b/include/MemPool.h
@@ -109,6 +109,7 @@ public:
     virtual void free(void *) = 0;
     virtual char const *objectType() const;
     virtual size_t objectSize() const = 0;
+    virtual int getInUseCount() = 0;
     int inUseCount();
     virtual void setChunkSize(size_t chunksize) {}
 private:
@@ -179,6 +180,7 @@ class MemImplementingAllocator : public MemAllocator
     /* Hint to the allocator - may be ignored */
     virtual void setChunkSize(size_t chunksize) {}
     virtual size_t objectSize() const;
+    virtual int getInUseCount() = 0;
   protected:
     virtual void *allocate() = 0;
     virtual void deallocate(void *) = 0;
@@ -204,6 +206,7 @@ class MemPool : public MemImplementingAllocator
     void createChunk();
     void *get();
     void push(void *obj);
+    virtual int getInUseCount();
   protected:
     virtual void *allocate();
     virtual void deallocate(void *);
@@ -230,9 +233,12 @@ class MemMalloc : public MemImplementingAllocator
     virtual bool idleTrigger(int shift) const;
     virtual void clean(time_t maxage);
     virtual int getStats(MemPoolStats * stats);
+    virtual int getInUseCount();
   protected:
     virtual void *allocate();
     virtual void deallocate(void *);
+  private:
+    int inuse;
 };
 
 class MemChunk
diff --git a/lib/MemPool.cc b/lib/MemPool.cc
index 5de67f74f5..26f40ae17c 100644
--- a/lib/MemPool.cc
+++ b/lib/MemPool.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: MemPool.cc,v 1.5 2006/09/03 04:11:59 hno Exp $
+ * $Id: MemPool.cc,v 1.6 2006/09/20 00:59:26 adrian Exp $
  *
  * DEBUG: section 63    Low Level Memory Pool Management
  * AUTHOR: Alex Rousskov, Andres Kroonmaa, Robert Collins
@@ -456,9 +456,7 @@ MemAllocator::objectType() const
 int
 MemAllocator::inUseCount()
 {
-    MemPoolStats stats;
-    getStats(&stats);
-    return stats.items_inuse;
+    return getInUseCount();
 }
 
 void
@@ -529,12 +527,14 @@ MemPools::flushMeters()
 void *
 MemMalloc::allocate()
 {
+    inuse++;
     return xcalloc(1, obj_size);
 }
 
 void
 MemMalloc::deallocate(void *obj)
 {
+    inuse--;
     xfree(obj);
 }
 
@@ -556,6 +556,12 @@ MemImplementingAllocator::free(void *obj)
     ++free_calls;
 }
 
+int
+MemPool::getInUseCount()
+{
+    return inuse;
+}
+
 void *
 MemPool::allocate()
 {
@@ -777,6 +783,12 @@ MemMalloc::getStats(MemPoolStats * stats)
     return getMeter().inuse.level;
 }
 
+int
+MemMalloc::getInUseCount()
+{
+	return inuse;
+}
+
 /*
  * Totals statistics is returned
  */
@@ -824,7 +836,7 @@ MemAllocator::MemAllocator(char const *aLabel) : label(aLabel)
 {
 }
 
-MemMalloc::MemMalloc(char const *label, size_t aSize) : MemImplementingAllocator(label, aSize) {}
+MemMalloc::MemMalloc(char const *label, size_t aSize) : MemImplementingAllocator(label, aSize) { inuse = 0; }
 
 bool
 MemMalloc::idleTrigger(int shift) const
diff --git a/src/MemObject.cc b/src/MemObject.cc
index 1dadcc3108..04fe0418f4 100644
--- a/src/MemObject.cc
+++ b/src/MemObject.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: MemObject.cc,v 1.23 2006/08/21 00:50:41 robertc Exp $
+ * $Id: MemObject.cc,v 1.24 2006/09/20 00:59:26 adrian Exp $
  *
  * DEBUG: section 19    Store Memory Primitives
  * AUTHOR: Robert Collins
@@ -68,11 +68,7 @@ RemovalPolicy * mem_policy = NULL;
 size_t
 MemObject::inUseCount()
 {
-    MemPoolStats stats;
-
-    Pool().getStats (&stats);
-
-    return stats.items_inuse;
+    return Pool().inUseCount();
 }
 
 MemObject::MemObject(char const *aUrl, char const *aLog_url)
diff --git a/src/mem_node.cc b/src/mem_node.cc
index d0dc18d02d..834aa5b5c1 100644
--- a/src/mem_node.cc
+++ b/src/mem_node.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: mem_node.cc,v 1.8 2005/11/02 22:19:22 serassio Exp $
+ * $Id: mem_node.cc,v 1.9 2006/09/20 00:59:27 adrian Exp $
  *
  * DEBUG: section 19    Store Memory Primitives
  * AUTHOR: Robert Collins
@@ -77,11 +77,7 @@ mem_node::~mem_node()
 size_t
 mem_node::InUseCount()
 {
-    MemPoolStats stats;
-
-    Pool().getStats (&stats);
-
-    return stats.items_inuse;
+    return Pool().inUseCount();
 }
 
 size_t
diff --git a/src/store.cc b/src/store.cc
index 473b543556..e6e036c110 100644
--- a/src/store.cc
+++ b/src/store.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: store.cc,v 1.600 2006/09/03 21:05:20 hno Exp $
+ * $Id: store.cc,v 1.601 2006/09/20 00:59:27 adrian Exp $
  *
  * DEBUG: section 20    Storage Manager
  * AUTHOR: Harvest Derived
@@ -210,12 +210,7 @@ StoreEntry::inUseCount()
 {
     if (!pool)
         return 0;
-
-    MemPoolStats stats;
-
-    pool->getStats (&stats);
-
-    return stats.items_inuse;
+    return pool->getInUseCount();
 }
 
 const char *