diff --git a/nczarr_test/CMakeLists.txt b/nczarr_test/CMakeLists.txt
index dc66e96bba..9a877e942a 100644
--- a/nczarr_test/CMakeLists.txt
+++ b/nczarr_test/CMakeLists.txt
@@ -120,6 +120,12 @@ IF(ENABLE_TESTS)
     TARGET_INCLUDE_DIRECTORIES(tst_chunkcases PUBLIC ../libnczarr)
     add_sh_test(nczarr_test run_chunkcases)
 
+    if(LARGE_FILE_TESTS)
+      BUILD_BIN_TEST(test_readcaching})
+      BUILD_BIN_TEST(test_writecaching})
+      add_sh_test(nczarr_test run_cachetest)
+    ENDIF()
+
     add_sh_test(nczarr_test run_purezarr)
     add_sh_test(nczarr_test run_interop)
     add_sh_test(nczarr_test run_misc)
diff --git a/nczarr_test/Makefile.am b/nczarr_test/Makefile.am
index f238adb98b..b605a2ab4a 100644
--- a/nczarr_test/Makefile.am
+++ b/nczarr_test/Makefile.am
@@ -34,9 +34,6 @@ ut_projections_SOURCES = ut_projections.c ${commonsrc}
 ut_chunking_SOURCES = ut_chunking.c ${commonsrc}
 tst_fillonlyz_SOURCES = tst_fillonlyz.c ${tstcommonsrc}
 
-check_PROGRAMS += test_readcaching test_writecaching
-TESTS += test_readcaching test_writecaching
-
 check_PROGRAMS += tst_zchunks tst_zchunks2 tst_zchunks3 tst_fillonlyz test_quantize tst_notzarr
 
 TESTS += run_ut_chunk.sh
@@ -69,6 +66,11 @@ TESTS += run_nulls.sh
 TESTS += run_notzarr.sh
 TESTS += run_external.sh
 
+if LARGE_FILE_TESTS
+check_PROGRAMS += test_writecaching test_readcaching
+TESTS += run_cachetest.sh
+endif
+
 endif #BUILD_UTILITIES
 
 if BUILD_UTILITIES 
diff --git a/nczarr_test/test_readcaching.c b/nczarr_test/test_readcaching.c
index ecfca615f1..29002b283e 100644
--- a/nczarr_test/test_readcaching.c
+++ b/nczarr_test/test_readcaching.c
@@ -1,8 +1,5 @@
-#include "netcdf.h"
-
 #include <stdlib.h>
 #include <stdio.h>
-
 #include <unistd.h>
 #include <sys/resource.h>
 
@@ -10,6 +7,15 @@
 #include <mach/mach.h>
 #endif
 
+#include "netcdf.h"
+
+#define filename "file://tmp_cachetest.zarr#mode=zarr,file"
+#define chunkSize (size_t)(1<<17) /* 128k */
+#define numCells (size_t)(50 * chunkSize)
+#define numSteps (size_t)360
+
+static float var[numCells];
+
 size_t getPeakRSS(void)
 {
   struct rusage rusage;
@@ -34,11 +40,6 @@ nce(int istat)
 int
 main(void)
 {
-  const char *filename = "file://tmp_readcaching.zarr#mode=zarr,file";
-  const size_t chunkSize = 262144; // 256k
-  const size_t numCells = 50 * chunkSize;
-  const size_t numSteps = 360;
-
   printf("read: chunkSize=%zu, numCells=%zu, numSteps=%zu, filename=%s\n", chunkSize, numCells, numSteps, filename);
 
   int ncId;
@@ -58,7 +59,6 @@ main(void)
   printf("set chunk cache: size=%zu, nelems=%zu, preemption=%g\n", size, nelems, preemption);
 
   {
-    float* var = calloc(sizeof(float),numCells);
     for (size_t i = 0; i < numCells; ++i) var[i] = 0.0f;
     for (size_t i = 0; i < numSteps; ++i)
       {
diff --git a/nczarr_test/test_writecaching.c b/nczarr_test/test_writecaching.c
index c2b9293332..a1d6b3e8b0 100644
--- a/nczarr_test/test_writecaching.c
+++ b/nczarr_test/test_writecaching.c
@@ -1,15 +1,20 @@
-#include "netcdf.h"
-
 #include <stdlib.h>
 #include <stdio.h>
-
 #include <unistd.h>
 #include <sys/resource.h>
-
 #if defined(__APPLE__) && defined(__MACH__)
 #include <mach/mach.h>
 #endif
 
+#include "netcdf.h"
+
+#define filename "file://tmp_cachetest.zarr#mode=zarr,file"
+#define chunkSize ((size_t)(1<<17)) /* 128k */
+#define numCells ((size_t)(50 * chunkSize))
+#define numSteps ((size_t)360)
+
+static float var[numCells];
+
 size_t getPeakRSS(void)
 {
   struct rusage rusage;
@@ -34,11 +39,6 @@ nce(int istat)
 int
 main(void)
 {
-  const char *filename = "file://tmp_writecaching.zarr#mode=zarr,file";
-  const size_t chunkSize = 262144; // 256k
-  const size_t numCells = 50 * chunkSize;
-  const size_t numSteps = 360;
-
   printf("write: chunkSize=%zu, numCells=%zu, numSteps=%zu, filename=%s\n", chunkSize, numCells, numSteps, filename);
 
   int ncId;
@@ -72,7 +72,6 @@ main(void)
   nce(nc_enddef(ncId));
 
   {
-    float* var = calloc(sizeof(float),numCells);
     for (size_t i = 0; i < numCells; ++i) var[i] = 0.0f;
     for (size_t i = 0; i < numSteps; ++i)
       {
@@ -92,7 +91,7 @@ main(void)
       printf("*** Failed: used: %luMB expected: < 100MB\n",mbused);
       return (1);
     } else {
-      printf("*** Passed: used: %luMB (< 100MB\)n",mbused);
+      printf("*** Passed: used: %luMB (< 100MB)\n",mbused);
       return 0;
     }
   }