diff --git a/configure.ac b/configure.ac
index 50d86b30c27..a83b53f817b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -51,6 +51,18 @@ if test "x$enable_logging" = xyes; then
    AC_DEFINE([PIO_ENABLE_LOGGING], 1, [If true, turn on logging.])
 fi
 
+# Does the user want to enable timing?
+AC_MSG_CHECKING([whether GPTL timing library is used])
+AC_ARG_ENABLE([timing],
+              [AS_HELP_STRING([--enable-timing],
+                              [enable use of the GPTL timing library.])])
+test "x$enable_timing" = xyes || enable_timing=no
+AC_MSG_RESULT([$enable_timing])
+if test "x$enable_timing" = xyes; then
+   AC_DEFINE([TIMING], 1, [If true, use GPTL timing library.])
+fi
+AM_CONDITIONAL(USE_GPTL, [test "x$enable_timing" = xyes])
+
 # Does the user want to enable Fortran library?
 AC_MSG_CHECKING([whether Fortran library should be build])
 AC_ARG_ENABLE([fortran],
@@ -148,6 +160,12 @@ fi
 #AC_CHECK_SIZEOF([MPI_Offset], [], [[#include <mpi.h>]])
 #AC_DEFINE([SIZEOF_MPI_OFFSET], [8], [netCDF classic library available])
 
+# If we want the timing library, we must find it.
+if test "x$enable_timing" = xyes; then
+   AC_CHECK_HEADERS([gptl.h])
+   AC_CHECK_LIB([gptl], [GPTLinitialize], [], [AC_MSG_ERROR([Can't find or link to the GPTL library.])])
+fi
+
 AC_CONFIG_FILES(src/flib/piodarray.F90:src/flib/piodarray.F90.in2)
 AC_CONFIG_FILES(src/flib/pionfatt_mod.F90:src/flib/pionfatt_mod.F90.in2)
 AC_CONFIG_FILES(src/flib/pionfget_mod.F90:src/flib/pionfget_mod.F90.in2)
@@ -165,11 +183,13 @@ AC_OUTPUT(Makefile
           src/Makefile
           src/clib/Makefile
           src/flib/Makefile
+          src/gptl/Makefile
           tests/Makefile
           tests/cunit/Makefile
           tests/unit/Makefile
           tests/general/Makefile
           tests/general/util/Makefile
+          tests/performance/Makefile
           doc/Makefile
           examples/Makefile
           examples/c/Makefile)
diff --git a/src/Makefile.am b/src/Makefile.am
index 68e4497dfb0..7cd8d61f77b 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -7,6 +7,10 @@ if BUILD_FORTRAN
 FLIB = flib
 endif
 
-SUBDIRS = clib $(FLIB)
+if USE_GPTL
+GPTL = gptl
+endif
+
+SUBDIRS = clib ${GPTL} $(FLIB)
 
 EXTRA_DIST = CMakeLists.txt
diff --git a/src/gptl/Makefile.am b/src/gptl/Makefile.am
new file mode 100644
index 00000000000..3bd4da9e0d5
--- /dev/null
+++ b/src/gptl/Makefile.am
@@ -0,0 +1,23 @@
+# This is part of PIO. It creates the Makefile for the GPTL directory.
+
+# Ed Hartnett 4/9/19
+
+# Turn off parallel builds in this directory.
+.NOTPARALLEL:
+
+# Build these uninstalled convenience libraries.
+noinst_LTLIBRARIES = libperf_utils.la libperf_mod.la
+
+# The convenience libraries depends on their source.
+libperf_utils_la_SOURCES = perf_utils.F90
+libperf_mod_la_SOURCES = perf_mod.F90
+
+# Each mod file depends on the .o file.
+perf_utils.mod: perf_utils.$(OBJEXT)
+perf_mod.mod: perf_mod.$(OBJEXT)
+
+# Does the user want to build fortran?
+#if BUILD_FORTRAN
+#endif
+
+EXTRA_DIST = CMakeLists.txt
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 7377b2aa9a5..a643bbcd976 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -8,8 +8,11 @@
 if BUILD_FORTRAN
 UNIT = unit
 GENERAL = general
+if USE_GPTL
+PERFORMANCE = performance
+endif
 endif
 
-SUBDIRS = cunit ${UNIT} ${GENERAL}
+SUBDIRS = cunit ${UNIT} ${GENERAL} ${PERFORMANCE}
 
 EXTRA_DIST = CMakeLists.txt
diff --git a/tests/performance/Makefile.am b/tests/performance/Makefile.am
new file mode 100644
index 00000000000..c02e9dad8a0
--- /dev/null
+++ b/tests/performance/Makefile.am
@@ -0,0 +1,27 @@
+## This is the automake file for building the Fortran performance
+## tests for the PIO library.
+
+# Ed Hartnett 4/6/19
+
+# Parallel builds don't currently work in this directory.
+.NOTPARALLEL:
+
+# Put together AM_CPPFLAGS and AM_LDFLAGS.
+include $(top_srcdir)/set_flags.am
+
+LDADD = libpio_tutil.la	\
+${top_builddir}/src/flib/libpiof.la		\
+${top_builddir}/src/clib/libpio.la
+
+# Build the test for make check.
+bin_PROGRAMS = pioperformance
+
+pioperformance_SOURCES = pioperformance.F90
+
+# Tests will run from a bash script.
+#TESTS = run_tests.sh
+
+EXTRA_DIST = CMakeLists.txt gensimple.pl
+
+# Clean up files produced during testing.
+CLEANFILES = *.nc *.log *.mod