Fix UHD buffering leading to out of memory

Since commit d9ef93e, UHD does not backpressure the modulator anymore.
If a pipe input is used, the ODR-DabMux before also doesn't get any
back-pressure, the modulation thread and the mux run a very high rate.

This high rate fills the buffer between OutputUHD and its worker thread,
until the out-of-memory killer kills ODR-DabMod.

Less impact on ZMQ input, because that is throttled at the mux, but
we still have a buffer that can grow in an uncontrolled way

1 files changed, 3 insertions, 6 deletions

diff --git a/src/OutputUHD.cpp b/src/OutputUHD.cpp
index 1b84b7c..8f988f3 100644
--- a/src/OutputUHD.cpp
+++ b/src/OutputUHD.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
    Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2014, 2015
+   Copyright (C) 2016
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -404,11 +404,8 @@ int OutputUHD::process(Buffer* dataIn, Buffer* dataOut)
         }
         else {
             while (true) {
-                if (uwd.frames.size() > FRAMES_MAX_SIZE) {
-                    usleep(10000); // 10ms
-                }
-
-                size_t num_frames = uwd.frames.push(frame);
+                size_t num_frames = uwd.frames.push_wait_if_full(frame,
+                        FRAMES_MAX_SIZE);
                 etiLog.log(trace, "UHD,push %zu", num_frames);
                 break;
             }