# HG changeset patch
# User Chris Cannam
# Date 1146773848 0
# Node ID 22494cc28c9f69d221d38f16f208912db0068cd3
# Parent  1aebdc68ec6de7af82b5f127010d10144f188075
* Reduce number of allocations and deallocations by keeping a spare buffer
  around (we were generally deallocating and then immediately allocating again,
  so it's much better not to have to bother as very large allocations can tie
  up the system)

diff -r 1aebdc68ec6d -r 22494cc28c9f base/MatrixFile.cpp
--- a/base/MatrixFile.cpp	Thu May 04 16:03:02 2006 +0000
+++ b/base/MatrixFile.cpp	Thu May 04 20:17:28 2006 +0000
@@ -38,9 +38,10 @@
     m_width(0),
     m_height(0),
     m_headerSize(2 * sizeof(size_t)),
-    m_defaultCacheWidth(256),
+    m_defaultCacheWidth(512),
     m_prevX(0),
-    m_requestToken(-1)
+    m_requestToken(-1),
+    m_spareData(0)
 {
     m_cache.data = 0;
 
@@ -90,10 +91,6 @@
     }
 
     m_fileName = fileName;
-    
-    //!!! why isn't this signal being delivered?
-    connect(&m_readThread, SIGNAL(cancelled(int)), 
-            this, SLOT(requestCancelled(int)));
 
     m_readThread.start();
 
@@ -118,8 +115,9 @@
     m_readThread.finish();
     m_readThread.wait();
 
-    if (requestData) delete[] requestData;
-    if (m_cache.data) delete[] m_cache.data;
+    if (requestData) free(requestData);
+    if (m_cache.data) free(m_cache.data);
+    if (m_spareData) free(m_spareData);
 
     if (m_fd >= 0) {
         if (::close(m_fd) < 0) {
@@ -408,7 +406,10 @@
                 
                 std::cerr << "actual: " << m_cache.x << ", " << m_cache.width << std::endl;
 
-                if (m_cache.data) delete[] m_cache.data;
+                if (m_cache.data) {
+                    if (m_spareData) free(m_spareData);
+                    m_spareData = (char *)m_cache.data;
+                }
                 m_cache.data = (float *)request.data;
 
                 m_readThread.done(m_requestToken);
@@ -427,7 +428,8 @@
             usleep(10000);
         }
 
-        delete[] ((float *)request.data);
+        if (m_spareData) free(m_spareData);
+        m_spareData = request.data;
         m_readThread.done(m_requestToken);
 
         m_requestToken = -1;
@@ -437,8 +439,9 @@
     request.mutex = &m_fdMutex;
     request.start = m_headerSize + rx * m_height * sizeof(float);
     request.size = rw * m_height * sizeof(float);
-    request.data = (char *)(new float[rw * m_height]);
+    request.data = (char *)realloc(m_spareData, rw * m_height * sizeof(float));
     MUNLOCK(request.data, rw * m_height * sizeof(float));
+    m_spareData = 0;
 
     m_requestingX = rx;
     m_requestingWidth = rw;
@@ -450,18 +453,6 @@
     m_requestToken = token;
 }
 
-void
-MatrixFile::requestCancelled(int token)
-{
-    std::cerr << "MatrixFile::requestCancelled(" << token << ")" << std::endl;
-
-    FileReadThread::Request request;
-    if (m_readThread.getRequest(token, request)) {
-        delete[] ((float *)request.data);
-        m_readThread.done(token);
-    }
-}
-
 bool
 MatrixFile::seekTo(size_t x, size_t y)
 {
diff -r 1aebdc68ec6d -r 22494cc28c9f base/MatrixFile.h
--- a/base/MatrixFile.h	Thu May 04 16:03:02 2006 +0000
+++ b/base/MatrixFile.h	Thu May 04 20:17:28 2006 +0000
@@ -45,9 +45,6 @@
     void setValueAt(size_t x, size_t y, float value);
     void setColumnAt(size_t x, float *values);
 
-protected slots:
-    void requestCancelled(int token);
-
 protected:
     int     m_fd;
     Mode    m_mode;
@@ -75,8 +72,10 @@
 
     FileReadThread m_readThread;
     int m_requestToken;
+
     size_t m_requestingX;
     size_t m_requestingWidth;
+    char *m_spareData;
 
     static std::map<QString, int> m_refcount;
     static QMutex m_refcountMutex;