From 157de9f3bbb23ed0439f85d9f99c86a90472de01 Mon Sep 17 00:00:00 2001
From: Gunnar Beutner <gunnar@beutner.name>
Date: Wed, 28 May 2014 15:57:48 +0200
Subject: [PATCH] Fix a situation where some threadpool work items are never
 executed.

Fixes #6349
---
 lib/base/threadpool.cpp | 5 +++--
 lib/base/threadpool.hpp | 4 +++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/base/threadpool.cpp b/lib/base/threadpool.cpp
index 6a7bf9fa2..365fe1fc9 100644
--- a/lib/base/threadpool.cpp
+++ b/lib/base/threadpool.cpp
@@ -272,8 +272,9 @@ void ThreadPool::ManagerThreadProc(void)
 				int tthreads = wthreads - alive;
 
 				/* Make sure there is at least one thread per CPU */
-				if (alive + tthreads < std::max(boost::thread::hardware_concurrency(), 4U))
-					tthreads = 1 - alive;
+				int ncput = std::max(boost::thread::hardware_concurrency() / QUEUECOUNT, 1U);
+				if (alive + tthreads < ncput)
+					tthreads = ncput - alive;
 
 				/* Don't kill more than 8 threads at once. */
 				if (tthreads < -8)
diff --git a/lib/base/threadpool.hpp b/lib/base/threadpool.hpp
index 27d9e53d3..518d7a14b 100644
--- a/lib/base/threadpool.hpp
+++ b/lib/base/threadpool.hpp
@@ -30,6 +30,8 @@
 namespace icinga
 {
 
+#define QUEUECOUNT 4
+
 /**
  * A thread pool.
  *
@@ -118,7 +120,7 @@ private:
 	boost::condition_variable m_MgmtCV;
 	bool m_Stopped;
 
-	Queue m_Queues[4];
+	Queue m_Queues[QUEUECOUNT];
 
 	void ManagerThreadProc(void);
 };
-- 
2.40.0