From 7bc90004e0214840664eb49ee8df5e273c24718c Mon Sep 17 00:00:00 2001
From: KongQun Yang <kqyang@google.com>
Date: Thu, 21 Jun 2018 17:38:47 -0700
Subject: [PATCH] Add IO Cache circular buffer full warning

Under VLOG(1).

IO Cache circular buffer full could result in UDP packet loss with UDP
inputs.

Related to #390 and #411.

Change-Id: Ia5636a70827978b5c2f71f6495256d758766632f
---
 packager/file/io_cache.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/packager/file/io_cache.cc b/packager/file/io_cache.cc
index 34b3b8382e..b2b1f866b0 100644
--- a/packager/file/io_cache.cc
+++ b/packager/file/io_cache.cc
@@ -72,6 +72,9 @@ uint64_t IoCache::Write(const void* buffer, uint64_t size) {
     AutoLock lock(lock_);
     while (!closed_ && (BytesFreeInternal() == 0)) {
       AutoUnlock unlock(lock_);
+      VLOG(1) << "Circular buffer is full, which can happen if data arrives "
+                 "faster than being consumed by packager. Ignore if it is not "
+                 "live packaging. Otherwise, try increasing --io_cache_size.";
       read_event_.Wait();
     }
     if (closed_)