Ticket #12045: 12045-try2.diff

mythtv/libs/libmythbase/threadedfilewriter.cpp

@@ -288 +288 @@
         left    -= towrite;
     }
 
-    LOG(VB_FILE, LOG_DEBUG, LOC + QString("Write(*, %1) total %2 cnt %3")
-            .arg(count,4).arg(totalBufferUse).arg(writeBuffers.size()));
+        //LOG(VB_FILE, LOG_DEBUG, LOC + QString("Write(*, %1) total %2 cnt %3")
+        //    .arg(count,4).arg(totalBufferUse).arg(writeBuffers.size()));
 
     return count;
 }
@@ -425 +425 @@
     MythTimer minWriteTimer;
     minWriteTimer.start();
 
+    uint64_t total_written = 0LL;
+
     while (!in_dtor)
     {
         if (ignore_writes)
@@ -518 +520 @@
             else
             {
                 tot += ret;
+                total_written += ret;
+                LOG(VB_FILE, LOG_DEBUG, LOC + QString("total written so far: %1 bytes").arg(total_written));
             }
 
             locker.relock();
@@ -604 +608 @@
     bool old = m_blocking;
     m_blocking = block;
     return old;
-}
- No newline at end of file
+}

mythtv/libs/libmythtv/fileringbuffer.cpp

@@ -4 +4 @@
 // POSIX C headers
 #include <sys/types.h>
 #include <sys/time.h>
+#include <sys/stat.h>
 #include <unistd.h>
 #include <fcntl.h>
 
@@ -437 +438 @@
  */
 int FileRingBuffer::safe_read(int fd, void *data, uint sz)
 {
-    int ret;
+    int ret, ret_select;
     unsigned tot = 0;
     unsigned errcnt = 0;
     unsigned zerocnt = 0;
@@ -452 +453 @@
     if (stopreads)
         return 0;
 
+    MythTimer t;
+    fd_set rfds;
+    struct timeval tv;
+    struct stat sb;
+    off_t current_pos = internalreadpos;
+
+    t.start();
+
     while (tot < sz)
     {
-        ret = read(fd2, (char *)data + tot, sz - tot);
-        if (ret < 0)
+        /* Wait up to 500 millisecond for a read. */
+        tv.tv_sec  = 0;
+        tv.tv_usec = 500 * 1000;
+        FD_ZERO(&rfds);
+        FD_SET(fd2, &rfds);
+
+        ret_select = select(fd2 + 1, &rfds, NULL, NULL, &tv);
+        if (ret_select == -1)
         {
-            if (errno == EAGAIN)
-                continue;
-
-            LOG(VB_GENERAL, LOG_ERR,
-                LOC + "File I/O problem in 'safe_read()'" + ENO);
-
-            errcnt++;
-            numfailures++;
-            if (errcnt == 3)
-                break;
+            LOG(VB_FILE, LOG_ERR, LOC + "select() errored");
+            break;
         }
-        else if (ret > 0)
+        else if (ret_select)
         {
-            tot += ret;
-        }
+            // check that we have some data to read, so we never read past
+            // the end of file
+            off_t toread = sz - tot;
 
-        if (oldfile)
-            break;
+            ret = fstat(fd2, &sb);
+            if (ret == 0)
+            {
+                if (current_pos >= sb.st_size)
+                {
+                    // simulate a EOF return
+                    ret = 0;
+                }
+                else
+                {
+                    toread = min(sb.st_size - current_pos, toread);
+                    LOG(VB_FILE, LOG_DEBUG, LOC +
+                        QString("read(%1) -- begin").arg(toread));
+                    ret = read(fd2, (char *)data + tot, toread);
+                    LOG(VB_FILE, LOG_DEBUG, LOC +
+                        QString("read(%1) -> %2 end").arg(toread).arg(ret));
+                }
+            }
 
-        if (ret == 0) // EOF returns 0
-        {
-            if (tot > 0)
-                break;
+            if (ret < 0)
+            {
+                if (errno == EAGAIN)
+                {
+                    continue;
+                }
 
-            zerocnt++;
+                LOG(VB_GENERAL, LOG_ERR,
+                    LOC + "File I/O problem in 'safe_read()'" + ENO);
 
-            // 0.36 second timeout for livetvchain with usleep(60000),
-            // or 2.4 seconds if it's a new file less than 30 minutes old.
-            if (zerocnt >= (livetvchain ? 6 : 40))
+                errcnt++;
+                numfailures++;
+                if (errcnt == 3)
+                    break;
+            }
+            else if (ret > 0)
             {
-                break;
+                tot += ret;
+                current_pos += tot;
+            }
+            else if (ret == 0) // EOF returns 0
+            {
+                if (tot > 0)
+                    break;
+
+                zerocnt++;
+
+                // 0.36 second timeout for livetvchain with usleep(60000),
+                // or 2.4 seconds if it's a new file less than 30 minutes old.
+                if (zerocnt >= (livetvchain ? 6 : 40))
+                {
+                    break;
+                }
+                if (tot < sz)
+                    usleep(60000);
             }
         }
+        else
+        {
+            LOG(VB_FILE, LOG_DEBUG,
+                LOC + QString("Nothing to read for %1ms").arg(t.elapsed()));
+            if (tot > 0)
+                break;
+        }
+
+        if (oldfile)
+            break;
+
         if (stopreads)
             break;
-        if (tot < sz)
-            usleep(60000);
     }
     return tot;
 }

mythtv/libs/libmythtv/ringbuffer.cpp

@@ -769 +769 @@
         if (PauseAndWait())
         {
             ignore_for_read_timing = true;
+            LOG(VB_FILE, LOG_DEBUG, LOC + "run: PauseAndWait Not reading continuing");
             continue;
         }
 
         long long totfree = ReadBufFree();
 
         const uint KB32 = 32*1024;
+
+//        if (totfree > ThreadedFileWriter::GetDefaultWriteBufferMinWriteSize())
+//        {
+//            totfree = ThreadedFileWriter::GetDefaultWriteBufferMinWriteSize();
+//        }
+
         // These are conditions where we don't want to go through
         // the loop if they are true.
         if (((totfree < KB32) && readsallowed) ||
@@ -783 +790 @@
             ignore_for_read_timing |=
                 (ignorereadpos >= 0) || commserror || stopreads;
             generalWait.wait(&rwlock, (stopreads) ? 50 : 1000);
+            LOG(VB_FILE, LOG_DEBUG, LOC + QString("run: Not reading continuing: totfree(%1) readsallowed(%2) ignorereadpos(%3) commserror(%4) stopreads(%5)")
+                .arg(totfree).arg(readsallowed).arg(ignorereadpos).arg(commserror).arg(stopreads));
             continue;
         }
 
@@ -898 +907 @@
                 }
                 rbwlock.unlock();
                 poslock.unlock();
+
+                LOG(VB_FILE, LOG_DEBUG, LOC + QString("total read so far: %1 bytes").arg(internalreadpos));
+                
             }
         }
+        else
+        {
+            LOG(VB_FILE, LOG_DEBUG, LOC + QString("We are not reading anything (totfree: %1 commserror:%2 ateof:%3 setswitchtonext:%4").arg(totfree).arg(commserror).arg(ateof).arg(setswitchtonext));
+        }
 
         int used = bufferSize - ReadBufFree();
 
@@ -1084 +1100 @@
             int elapsed = t.elapsed();
             if (elapsed > 500 && low_buffers && avail >= fill_min)
                 count = avail;
-            else if  (((elapsed > 250) && (elapsed < 500))  ||
-                     ((elapsed >  500) && (elapsed < 750))  ||
+            else if  (((elapsed > 500) && (elapsed < 750))  ||
                      ((elapsed > 1000) && (elapsed < 1250)) ||
                      ((elapsed > 2000) && (elapsed < 2250)) ||
                      ((elapsed > 4000) && (elapsed < 4250)) ||
                      ((elapsed > 8000) && (elapsed < 8250)) ||
                      ((elapsed > 9000)))
             {
+                LOG(VB_FILE, LOG_DEBUG,
+                    LOC + QString("used = %1").arg(bufferSize - ReadBufFree()));
                 LOG(VB_GENERAL, LOG_INFO, LOC + "Waited " +
                     QString("%1").arg((elapsed / 250) * 0.25f, 3, 'f', 1) +
                     " seconds for data \n\t\t\tto become available..." +