Yield instead of busy-waiting on fences for NVIDIA cards.

[nageru] / quicksync_encoder.cpp

diff --git a/quicksync_encoder.cpp b/quicksync_encoder.cpp
index 1b36aa5246fbda3b19b5e65a5abc48365ab23840..6cab461a98fe37bbb87a5c0e301829fa31162fb2 100644 (file)
--- a/quicksync_encoder.cpp
+++ b/quicksync_encoder.cpp
@@ -1981,8 +1981,12 @@ void QuickSyncEncoderImpl::pass_frame(QuickSyncEncoderImpl::PendingFrame frame,
        // Wait for the GPU to be done with the frame.
        GLenum sync_status;
        do {
-               sync_status = glClientWaitSync(frame.fence.get(), 0, 1000000000);
+               sync_status = glClientWaitSync(frame.fence.get(), 0, 0);
                check_error();
+               if (sync_status == GL_TIMEOUT_EXPIRED) {
+                       // NVIDIA likes to busy-wait; yield instead.
+                       this_thread::sleep_for(milliseconds(1));
+               }
        } while (sync_status == GL_TIMEOUT_EXPIRED);
        assert(sync_status != GL_WAIT_FAILED);