Merge pull request #274 from dongahn/planner2

planner: initial planner work

Makefile.am

@@ -1,7 +1,7 @@
 
 ACLOCAL_AMFLAGS = -I m4
 
-SUBDIRS = src rdl resrc simulator sched etc t
+SUBDIRS = src rdl resrc resource simulator sched etc t
 
 EXTRA_DIST= \
 	conf \

configure.ac

@@ -101,10 +101,14 @@ AC_CONFIG_FILES([Makefile
   src/common/libtap/Makefile
   src/common/liblsd/Makefile
   src/common/libutil/Makefile
+  src/common/librbtree/Makefile
   rdl/Makefile
   rdl/test/Makefile
   resrc/Makefile
   resrc/test/Makefile
+  resource/Makefile
+  resource/planner/Makefile
+  resource/planner/test/Makefile
   sched/Makefile
   simulator/Makefile
   etc/Makefile
@@ -116,8 +120,10 @@ echo "
   Prefix...........: $prefix
   Debug Build......: $debug
   C Compiler.......: $CC
+  C++ Compiler.....: $CXX
   CFLAGS...........: $CFLAGS
   CPPFLAGS.......... $CPPFLAGS
+  CXXFLAGS.......... $CXXFLAGS
   FLUX.............: $FLUX
   FLUX_CORE_CFLAGS.: $FLUX_CORE_CFLAGS
   FLUX_CORE_LIBS...: $FLUX_CORE_LIBS

resource/Makefile.am

@@ -0,0 +1 @@
+SUBDIRS = . planner

resource/planner/Makefile.am

@@ -0,0 +1,22 @@
+AM_CFLAGS = \
+	$(WARNING_CFLAGS) \
+	$(CODE_COVERAGE_CFLAGS)
+
+AM_CPPFLAGS = \
+	-I$(top_srcdir) \
+	$(CZMQ_CFLAGS)
+
+AM_LDFLAGS = \
+	$(CODE_COVERAGE_LDFLAGS)
+
+SUBDIRS = . test
+
+noinst_LTLIBRARIES = libplanner.la
+noinst_HEADERS = planner.h
+
+libplanner_la_SOURCES = planner.c
+libplanner_la_CFLAGS = $(AM_CFLAGS) -I$(top_srcdir)/resource/planner
+libplanner_la_LIBADD = \
+	$(top_builddir)/src/common/libutil/libutil.la \
+	$(top_builddir)/src/common/librbtree/librbtree.la \
+	$(CZMQ_LIBS)

resource/planner/README.md

@@ -0,0 +1,64 @@
+### PLANNER API
+
+Planner provides a simple abstraction and efficient mechanisms
+to keep track of the resource states for batch-job scheduling.
+Its API builds on two simple concepts:
+
+- Planner: just like your calendar planner, a planner object
+allows you to update and query the available resource states over
+time (i.e., integer unit-less time).
+
+- Span: just like you mark your activities over consecutive days
+in your calendar planner with a span, a span
+allows you to update your resource uses using a start time,
+duration and resource requirement.
+
+Planner is designed for speed. Specifically,
+it uses Linux OS kernel's red-black binary search tree code
+to update and query the resource states over time.
+It manages each of the two scheduled points of spans
+using two highly efficient binary search trees:
+
+- Scheduled point red-black binary search tree [1,2]
+- Min-time resource augmented red-black search tree [1,2]
+
+The scheduled-point search tree allows the planner to find the
+accurate resource state of any given instant time with
+(`O(log n)`) complexity.
+On the other hand, the min-time resource tree enables you to find
+the earliest scheduable point where your resource
+requirement can be satisfied also with (`O(log n)`) complexity.
+Say, you have a total of 10 available resource units and have
+allocated 5 units between time t1 and t2,
+[t1, t2), as well as 3 units from time t2 to t3, [t2, t3).
+Subsequently, you want to find about the earliest scheduled point at which you
+can allocate 7 units. The min-time tree will answer t2 as the
+earliest point in `O(log N)`. By contrast, a request for 5 units
+will be resolved to t1 with the same performance guarantee.
+Using both of these search trees, you can efficiently operate
+on the planner over both the time and resource dimensions alike.
+
+Planner was born out of real-world needs in Flux's
+batch-job scheduling infrastructure. As high performance
+computing (HPC) is undergoing significant changes
+in both performance-limiting resource types
+and workloads, simple data models
+(e.g., bitmaps) representing HPC compute and other
+consumable resources present increasingly greater
+challenges for effective scheduling. In response,
+Flux is in the process of modeling complex HPC
+resources using a graph. While this
+allows a highly sophisticated resource selections,
+it can be done at the expense of excessive, highly
+time-consuming searches of a large graph.
+Planner is specifically designed to mitigate
+the scalability and performance risk of such a graph-based
+approach by allowing our schedulers to prune the search
+space of a graph more aggressively.
+
+[1] Red-black tree (Visited 9/27/2017), Wikipedia,
+https://en.wikipedia.org/wiki/Red-black_tree
+
+[2] Red-black Trees (restorer) in Linux (Visited 9/27/2017), Rob Landley,
+https://www.kernel.org/doc/Documentation/rbtree.txt
+