diff --git a/util/partitioned_counter.cc b/util/partitioned_counter.cc
index bd2af7d523c..64aa348609b 100644
--- a/util/partitioned_counter.cc
+++ b/util/partitioned_counter.cc
@@ -205,13 +205,12 @@ static pthread_key_t thread_destructor_key;
 //******************************************************************************
 
 GrowableArray<bool> counters_in_use;
-//bool *counters_in_use = NULL;
-//uint64_t counters_in_use_size = 0;
 
 static uint64_t allocate_counter (void)
 // Effect: Find an unused counter number, and allocate it, returning the counter number.
-// Requires: The pc mutex is held before calling.
+//  Grabs the pc_lock.
 {
+    pc_lock();    
     size_t size = counters_in_use.get_size();
     for (uint64_t i=0; i<size; i++) {
         if (!counters_in_use.fetch_unchecked(i)) {
@@ -220,6 +219,7 @@ static uint64_t allocate_counter (void)
         }
     }
     counters_in_use.push(true);
+    pc_unlock();    
     return size;
 }
 
diff --git a/util/tests/CMakeLists.txt b/util/tests/CMakeLists.txt
index 4f1d0c9b434..505432403f5 100644
--- a/util/tests/CMakeLists.txt
+++ b/util/tests/CMakeLists.txt
@@ -12,6 +12,7 @@ if(BUILD_TESTING)
 
   add_helgrind_test(util/helgrind_test_partitioned_counter $<TARGET_FILE:test_partitioned_counter>)
   add_helgrind_test(util/helgrind_test_circular_buffer $<TARGET_FILE:test_circular_buffer>)
+  add_helgrind_test(util/helgrind_test_partitioned_counter_5833 $<TARGET_FILE:test_partitioned_counter_5833>)
 
   foreach(test ${tests})
     add_test(util/${test} ${test})
diff --git a/util/tests/test_partitioned_counter_5833.cc b/util/tests/test_partitioned_counter_5833.cc
new file mode 100644
index 00000000000..3c62a58bb1c
--- /dev/null
+++ b/util/tests/test_partitioned_counter_5833.cc
@@ -0,0 +1,70 @@
+/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+// vim: ft=cpp:expandtab:ts=8:sw=4:softtabstop=4:
+#ident "$Id$"
+#ident "Copyright (c) 2007-2012 Tokutek Inc.  All rights reserved."
+#ident "The technology is licensed by the Massachusetts Institute of Technology, Rutgers State University of New Jersey, and the Research Foundation of State University of New York at Stony Brook under United States of America Serial No. 11/760379 and to the patents and/or patent applications resulting from it."
+
+// Demonstrate a race if #5833 isn't fixed.
+
+#include <pthread.h>
+#include <toku_portability.h>
+#include <util/partitioned_counter.h>
+#include "test.h"
+
+
+static void pt_create (pthread_t *thread, void *(*f)(void*), void *extra) {
+    int r = pthread_create(thread, NULL, f, extra);
+    assert(r==0);
+}
+
+static void pt_join (pthread_t thread, void *expect_extra) {
+    void *result;
+    int r = pthread_join(thread, &result);
+    assert(r==0);
+    assert(result==expect_extra);
+}
+
+static int verboseness_cmdarg=0;
+
+static void parse_args (int argc, const char *argv[]) {
+    const char *progname = argv[1];
+    argc--; argv++;
+    while (argc>0) {
+	if (strcmp(argv[0], "-v")==0) verboseness_cmdarg++;
+	else {
+	    printf("Usage: %s [-v]\n", progname);
+	    exit(1);
+	}
+	argc--; argv++;
+    }
+}
+
+#define NCOUNTERS 2
+PARTITIONED_COUNTER array_of_counters[NCOUNTERS];
+
+static void *counter_init_fun(void *tnum_pv) {
+    int *tnum_p = (int*)tnum_pv;
+    int tnum = *tnum_p;
+    assert(0<=tnum  && tnum<NCOUNTERS);
+    array_of_counters[tnum] = create_partitioned_counter();
+    return tnum_pv;
+}
+
+static void do_test_5833(void) {
+    pthread_t threads[NCOUNTERS];
+    int       tids[NCOUNTERS];
+    for (int i=0; i<NCOUNTERS; i++) {
+        tids[i] = i;
+        pt_create(&threads[i], counter_init_fun, &tids[i]);
+    }
+    for (int i=0; i<NCOUNTERS; i++) {
+        pt_join(threads[i], &tids[i]);
+        destroy_partitioned_counter(array_of_counters[i]);
+    }
+}
+
+int test_main(int argc, const char *argv[]) {
+    parse_args(argc, argv);
+    do_test_5833();
+    return 0;
+}