[vlc-commits] demux: adaptive: compute latency from request

[Francois Cartegnie]

vlc | branch: master | Francois Cartegnie <fcvlcdev at free.fr> | Wed Mar  3 14:00:31 2021 +0100| [e8c855dea80be91bba876e4c4709e4022e479f6e] | committer: Francois Cartegnie

demux: adaptive: compute latency from request

> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=e8c855dea80be91bba876e4c4709e4022e479f6e
---

 modules/demux/adaptive/http/Chunk.cpp | 34 +++++++++++++++++++++-------------
 modules/demux/adaptive/http/Chunk.h   |  4 +++-
 2 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/modules/demux/adaptive/http/Chunk.cpp b/modules/demux/adaptive/http/Chunk.cpp
index b138b26f9c..663d318aaa 100644
--- a/modules/demux/adaptive/http/Chunk.cpp
+++ b/modules/demux/adaptive/http/Chunk.cpp
@@ -210,23 +210,29 @@ block_t * HTTPChunkSource::read(size_t readsize)
         return nullptr;
     }
 
-    vlc_tick_t time = vlc_tick_now();
     ssize_t ret = connection->read(p_block->p_buffer, readsize);
-    time = vlc_tick_now() - time;
     if(ret < 0)
     {
         block_Release(p_block);
         p_block = nullptr;
         eof = true;
+        downloadEndTime = vlc_tick_now();
     }
     else
     {
         p_block->i_buffer = (size_t) ret;
         consumed += p_block->i_buffer;
         if((size_t)ret < readsize)
+        {
             eof = true;
-        if(ret && time && type == ChunkType::Segment)
-            connManager->updateDownloadRate(sourceid, p_block->i_buffer, time);
+            downloadEndTime = vlc_tick_now();
+        }
+        if(ret && p_block->i_buffer &&
+           downloadEndTime > requestStartTime && type == ChunkType::Segment)
+        {
+            connManager->updateDownloadRate(sourceid, p_block->i_buffer,
+                                            downloadEndTime - requestStartTime);
+        }
     }
 
     return p_block;
@@ -251,6 +257,8 @@ bool HTTPChunkSource::prepare()
 
     ConnectionParams connparams = params; /* can be changed on 301 */
 
+    requestStartTime = vlc_tick_now();
+
     unsigned int i_redirects = 0;
     while(i_redirects++ < HTTPConnection::MAX_REDIRECTS)
     {
@@ -281,6 +289,7 @@ bool HTTPChunkSource::prepare()
                from content length */
         contentLength = connection->getContentLength();
         prepared = true;
+        responseTime = vlc_tick_now();
         return true;
     }
 
@@ -303,7 +312,6 @@ HTTPChunkBufferedSource::HTTPChunkBufferedSource(const std::string& url, Abstrac
     done = false;
     eof = false;
     held = false;
-    downloadstart = 0;
 }
 
 HTTPChunkBufferedSource::~HTTPChunkBufferedSource()
@@ -374,7 +382,8 @@ void HTTPChunkBufferedSource::bufferize(size_t readsize)
     {
         size_t size;
         vlc_tick_t time;
-    } rate = {0,0};
+        vlc_tick_t latency;
+    } rate = {0,0,0};
 
     ssize_t ret = connection->read(p_block->p_buffer, readsize);
     if(ret <= 0)
@@ -383,9 +392,10 @@ void HTTPChunkBufferedSource::bufferize(size_t readsize)
         p_block = nullptr;
         mutex_locker locker {lock};
         done = true;
+        downloadEndTime = vlc_tick_now();
         rate.size = buffered + consumed;
-        rate.time = vlc_tick_now() - downloadstart;
-        downloadstart = 0;
+        rate.time = downloadEndTime - requestStartTime;
+        rate.latency = responseTime - requestStartTime;
     }
     else
     {
@@ -396,9 +406,10 @@ void HTTPChunkBufferedSource::bufferize(size_t readsize)
         if((size_t) ret < readsize)
         {
             done = true;
+            downloadEndTime = vlc_tick_now();
             rate.size = buffered + consumed;
-            rate.time = vlc_tick_now() - downloadstart;
-            downloadstart = 0;
+            rate.time = downloadEndTime - requestStartTime;
+            rate.latency = responseTime - requestStartTime;
         }
     }
 
@@ -413,10 +424,7 @@ void HTTPChunkBufferedSource::bufferize(size_t readsize)
 bool HTTPChunkBufferedSource::prepare()
 {
     if(!prepared)
-    {
-        downloadstart = vlc_tick_now();
         return HTTPChunkSource::prepare();
-    }
     return true;
 }
 
diff --git a/modules/demux/adaptive/http/Chunk.h b/modules/demux/adaptive/http/Chunk.h
index bcfa8dc468..c596c953fd 100644
--- a/modules/demux/adaptive/http/Chunk.h
+++ b/modules/demux/adaptive/http/Chunk.h
@@ -120,6 +120,9 @@ namespace adaptive
                 bool                eof;
                 ID                  sourceid;
                 ChunkType           type;
+                vlc_tick_t          requestStartTime;
+                vlc_tick_t          responseTime;
+                vlc_tick_t          downloadEndTime;
 
             private:
                 bool init(const std::string &);
@@ -151,7 +154,6 @@ namespace adaptive
                 size_t              buffered; /* read cache size */
                 bool                done;
                 bool                eof;
-                vlc_tick_t          downloadstart;
                 vlc::threads::condition_variable avail;
                 bool                held;
         };