PR 831 Inclusions (credit goes to bobo1on1):

- Use Free Ram Percentage as Buffer Size
- Adjust Read Rate Based On Max Bitrate

Enhancements to PR 831:

- move variables over to advanced settings under <network> section ("alwaysforcebuffer" default false and "freememorycachepercent" default 50% max 80% with hard limit of 1GB and 0 value will force filecache. It also removes "cachemembuffersize" variable as it is no longer needed)

- "alwaysforcebuffer" variable will cache everything run through dvdplayer (i.e. OS network shares, local media, etc) except Optical Media Drives

- Memory buffer is straight percentage of free ram (i.e. if 50% free ram is used ~75% of the 50% will be forward looking buffer and ~25% of the 50% will be back buffer)

- Rate limiting which fixes SMB issues with PR 831 as far as I can tell (1.25 times max bitrate up to 40 MB/s in which case it is throttled to max bitrate)

- ios and linux fixes

Advanced Settings Notes: This PR adds 2 setting under advanced settings and removes the "cachemembuffersize" setting as it is no longer needed. The added settings are as follows:

1. alwaysforcebuffer: This will force everything ran through dvdplayer to be buffered that would not be normal buffered except Optical Media.  This includes SMB, Local Files, OS Network Shares, etc.  The current default is false due to it not really being a help to people who use hardwired connections (as they probably do not need buffering for SMB, etc).

2. "freememorycachepercent": The amount of free memory to use as buffer size.  Please note that of the percentage of free memory used ~75% will be used for forward buffering and ~25% will be used for the back buffer.  The default is 50% which is a good default for memory limted devices such as the atv2.  The max is 80 percent and there is a hard limit of 1GB buffer size irregardless of free ram.  Setting it to 0 will force filecaching (same as the way cachemembuffersize was used)

Merged again

xbmc/cores/dvdplayer/DVDInputStreams/DVDInputStreamFile.cpp

@@ -23,6 +23,7 @@
 #include "filesystem/IFile.h"
 #include "utils/log.h"
 #include "utils/URIUtils.h"
+#include "settings/AdvancedSettings.h"  
 
 using namespace XFILE;
 
@@ -51,8 +52,13 @@ bool CDVDInputStreamFile::Open(const char* strFile, const std::string& content)
   if (!m_pFile)
     return false;
 
+  unsigned int flags = READ_TRUNCATED | READ_BITRATE | READ_CHUNKED;
+
+  if (!URIUtils::IsOnDVD(strFile) && !URIUtils::IsBluray(strFile) && g_advancedSettings.m_alwaysForceBuffer)
+    flags |= READ_CACHED;
+
   // open file in binary mode
-  if (!m_pFile->Open(strFile, READ_TRUNCATED | READ_BITRATE | READ_CHUNKED))
+  if (!m_pFile->Open(strFile, flags))
   {
     delete m_pFile;
     m_pFile = NULL;
@@ -144,6 +150,7 @@ int CDVDInputStreamFile::GetBlockSize()
 void CDVDInputStreamFile::SetReadRate(unsigned rate)
 {
   unsigned maxrate = rate + 1024 * 1024 / 8;
+  CLog::Log(LOGDEBUG, "CDVDInputStreamFile::SetReadRate - Read rate set to %u bytes per second", maxrate);
   if(m_pFile->IoControl(IOCTRL_CACHE_SETRATE, &maxrate) >= 0)
     CLog::Log(LOGDEBUG, "CDVDInputStreamFile::SetReadRate - set cache throttle rate to %u bytes per second", maxrate);
 }

xbmc/cores/dvdplayer/DVDPlayer.cpp

@@ -419,6 +419,7 @@ CDVDPlayer::CDVDPlayer(IPlayerCallback& callback)
   m_offset_pts = 0.0;
   m_playSpeed = DVD_PLAYSPEED_NORMAL;
   m_caching = CACHESTATE_DONE;
+  m_readrate = 0;
 
   memset(&m_SpeedState, 0, sizeof(m_SpeedState));
 
@@ -676,7 +677,11 @@ bool CDVDPlayer::OpenDemuxStream()
   int64_t len = m_pInputStream->GetLength();
   int64_t tim = m_pDemuxer->GetStreamLength();
   if(len > 0 && tim > 0)
-    m_pInputStream->SetReadRate(len * 1000 / tim);
+  {	
+    //cap to intital read rate to 40 megabits/second if less than average bitrate * 1.25
+    m_readrate = std::min((unsigned int)((len * 1000 / tim) * 1.25), (unsigned int) (40000000 / 8));
+    m_pInputStream->SetReadRate(m_readrate);
+  }
 
   return true;
 }
@@ -1075,7 +1080,10 @@ void CDVDPlayer::Process()
 
     // update application with our state
     UpdateApplication(1000);
-
+
+    //update readrate based on peak bitrate
+    UpdateReadRate();	
+
     if (CheckDelayedChannelEntry())
       continue;
 
@@ -3926,6 +3934,20 @@ void CDVDPlayer::UpdateApplication(double timeout)
   m_UpdateApplication = CDVDClock::GetAbsoluteClock();
 }
 
+void CDVDPlayer::UpdateReadRate()
+{
+  unsigned int bytespersecond = (GetVideoBitrate() + GetAudioBitrate()) / 8;
+
+  if (bytespersecond > m_readrate)
+  {  
+    //if current bitrate * 1.25 is over 40 Mbs then cap at at max of actual bitrate or 40 Mb/s whichever is greater
+    //otherwise set read rate to current bitrate * 1.25
+    m_readrate = std::min((unsigned int)(bytespersecond * 1.25), std::max((unsigned int) bytespersecond, (unsigned int) (40000000 / 8)));
+
+    m_pInputStream->SetReadRate(m_readrate);
+  }
+}
+
 bool CDVDPlayer::CanRecord()
 {
   CSingleLock lock(m_StateSection);

xbmc/cores/dvdplayer/DVDPlayer.h

@@ -338,6 +338,7 @@ class CDVDPlayer : public IPlayer, public CThread, public IDVDPlayer
 
   void UpdateApplication(double timeout);
   void UpdatePlayState(double timeout);
+  void UpdateReadRate();
   double m_UpdateApplication;
 
   bool m_bAbortRequest;
@@ -347,7 +348,7 @@ class CDVDPlayer : public IPlayer, public CThread, public IDVDPlayer
   ECacheState  m_caching;
   CFileItem    m_item;
   unsigned int m_iChannelEntryTimeOut;
-
+  unsigned int m_readrate;
 
   CCurrentStream m_CurrentAudio;
   CCurrentStream m_CurrentVideo;

xbmc/filesystem/FileCache.cpp

@@ -18,6 +18,7 @@
  *
  */
 
+#include <limits.h>
 #include "threads/SystemClock.h"
 #include "utils/AutoPtrHandle.h"
 #include "FileCache.h"
@@ -85,11 +86,27 @@ CFileCache::CFileCache() : CThread("CFileCache")
    m_seekPos = 0;
    m_readPos = 0;
    m_writePos = 0;
-   if (g_advancedSettings.m_cacheMemBufferSize == 0)
+   if (g_advancedSettings.m_freeMemCachePercent == 0)
      m_pCache = new CSimpleFileCache();
    else
-     m_pCache = new CCircularCache(g_advancedSettings.m_cacheMemBufferSize
-                                 , std::max<unsigned int>( g_advancedSettings.m_cacheMemBufferSize / 4, 1024 * 1024));
+   {
+     //set cache size of m_freeMemCachePercent of free ram,  with hardcoded 1 GB upper limit
+     MEMORYSTATUSEX stat;
+     stat.dwLength = sizeof(MEMORYSTATUSEX);
+     GlobalMemoryStatusEx(&stat);
+
+     //limit max cache to 1 GB
+     unsigned int maxcache = (1024 * 1024 * 1000);
+     double ramamount = (stat.ullAvailPhys * (g_advancedSettings.m_freeMemCachePercent / 100.00));
+
+     unsigned int cacheRam = std::min(static_cast<unsigned int>(ramamount), maxcache);
+
+     unsigned int frontCache = static_cast<unsigned int>(cacheRam * 0.75);
+     unsigned int backCache = cacheRam - frontCache;
+
+     m_pCache = new CCircularCache(frontCache, std::max<unsigned int>(backCache, 1024 * 1024));
+   }
+
    m_seekPossible = 0;
    m_cacheFull = false;
 }

xbmc/filesystem/MemBufferCache.cpp

@@ -38,9 +38,9 @@ MemBufferCache::MemBufferCache()
  : CCacheStrategy()
 {
   m_nStartPosition = 0;
-  m_buffer.Create(g_advancedSettings.m_cacheMemBufferSize + 1);
-  m_HistoryBuffer.Create(g_advancedSettings.m_cacheMemBufferSize + 1);
-  m_forwardBuffer.Create(g_advancedSettings.m_cacheMemBufferSize + 1);
+  m_buffer.Create((1024 * 1024 * 10) + 1);
+  m_HistoryBuffer.Create((1024 * 1024 * 10) + 1);
+  m_forwardBuffer.Create((1024 * 1024 * 10) + 1);
 }
 
 

xbmc/settings/AdvancedSettings.cpp

@@ -298,7 +298,8 @@ void CAdvancedSettings::Initialize()
 
   m_measureRefreshrate = false;
 
-  m_cacheMemBufferSize = 1024 * 1024 * 20;
+  m_alwaysForceBuffer = false;
+  m_freeMemCachePercent = 50;
   m_addonPackageFolderSize = 200;
 
   m_jsonOutputCompact = true;
@@ -684,11 +685,12 @@ void CAdvancedSettings::ParseSettingsFile(const CStdString &file)
   pElement = pRootElement->FirstChildElement("network");
   if (pElement)
   {
+    XMLUtils::GetBoolean(pElement, "alwaysforcebuffer", m_alwaysForceBuffer);
     XMLUtils::GetInt(pElement, "curlclienttimeout", m_curlconnecttimeout, 1, 1000);
     XMLUtils::GetInt(pElement, "curllowspeedtime", m_curllowspeedtime, 1, 1000);
     XMLUtils::GetInt(pElement, "curlretries", m_curlretries, 0, 10);
     XMLUtils::GetBoolean(pElement,"disableipv6", m_curlDisableIPV6);
-    XMLUtils::GetUInt(pElement, "cachemembuffersize", m_cacheMemBufferSize);
+    XMLUtils::GetInt(pElement, "freememorycachepercent", m_freeMemCachePercent, 0, 80);
   }
 
   pElement = pRootElement->FirstChildElement("jsonrpc");

xbmc/settings/AdvancedSettings.h

@@ -349,7 +349,8 @@ class CAdvancedSettings
     int  m_guiDirtyRegionNoFlipTimeout;
     unsigned int m_addonPackageFolderSize;
 
-    unsigned int m_cacheMemBufferSize;
+    bool m_alwaysForceBuffer;
+    int m_freeMemCachePercent;
 
     bool m_jsonOutputCompact;
     unsigned int m_jsonTcpPort;