Import Debian changes 0.7.1-2

elki (0.7.1-2) unstable; urgency=low

  * Cherry-pick bugfix for single-core systems (Closes: #834739)

3 files changed, 72 insertions, 0 deletions

diff --git a/debian/changelog b/debian/changelog
index 5e9c2b47..0b357042 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+elki (0.7.1-2) unstable; urgency=low
+
+  * Cherry-pick bugfix for single-core systems (Closes: #834739)
+
+ -- Erich Schubert <erich@debian.org>  Sun, 25 Sep 2016 15:27:58 +0200
+
 elki (0.7.1-1) unstable; urgency=low
 
   * New upstream release (mostly bug fixes)
diff --git a/debian/patches/series b/debian/patches/series
index 33fc6161..8af3738a 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1,2 +1,3 @@
 build.patch
 better-classpath.patch
+single-core-bugfix.patch
diff --git a/debian/patches/single-core-bugfix.patch b/debian/patches/single-core-bugfix.patch
new file mode 100644
index 00000000..f4a18d0e
--- /dev/null
+++ b/debian/patches/single-core-bugfix.patch
@@ -0,0 +1,65 @@
+From 48e82af606d4c6c133a50405a23a645391f55d80 Mon Sep 17 00:00:00 2001
+From: Erich Schubert <schube@dbs.ifi.lmu.de>
+Date: Thu, 30 Jun 2016 14:38:55 +0200
+Subject: [PATCH] Bug fix for single-core CPUs.
+
+---
+ .../de/lmu/ifi/dbs/elki/parallel/ParallelExecutor.java   | 16 ++++++++--------
+ 1 file changed, 8 insertions(+), 8 deletions(-)
+
+--- a/elki/src/main/java/de/lmu/ifi/dbs/elki/parallel/ParallelExecutor.java
++++ b/elki/src/main/java/de/lmu/ifi/dbs/elki/parallel/ParallelExecutor.java
+@@ -40,19 +40,19 @@
+ 
+ /**
+  * Class to run processors in parallel, on all available cores.
+- * 
++ *
+  * TODO: add progress
+- * 
++ *
+  * @author Erich Schubert
+  * @since 0.7.0
+- * 
++ *
+  * @apiviz.has BlockArrayRunner
+  * @apiviz.uses ParallelCore
+  */
+ public class ParallelExecutor {
+   /**
+    * Run a task on all available CPUs.
+-   * 
++   *
+    * @param ids IDs to process
+    * @param procs Processors to run
+    */
+@@ -65,7 +65,7 @@
+       core.connect();
+       int numparts = core.getParallelism();
+       // TODO: are there better heuristics for choosing this?
+-      numparts = (size > numparts * numparts * 16) ? numparts * numparts - 1 : numparts;
++      numparts = (size > numparts * numparts * 16) ? numparts * Math.max(1, numparts - 1) : numparts;
+ 
+       final int blocksize = (size + (numparts - 1)) / numparts;
+       List<Future<ArrayDBIDs>> parts = new ArrayList<>(numparts);
+@@ -93,9 +93,9 @@
+ 
+   /**
+    * Run for an array part, without step size.
+-   * 
++   *
+    * @author Erich Schubert
+-   * 
++   *
+    * @apiviz.uses Processor
+    */
+   protected static class BlockArrayRunner implements Callable<ArrayDBIDs>, Executor {
+@@ -126,7 +126,7 @@
+ 
+     /**
+      * Constructor.
+-     * 
++     *
+      * @param ids IDs to process
+      * @param start Starting position
+      * @param end End position