diff --git a/nfs4.1/server41tests/st_flex.py b/nfs4.1/server41tests/st_flex.py
index 06dbba8..a14c926 100644
--- a/nfs4.1/server41tests/st_flex.py
+++ b/nfs4.1/server41tests/st_flex.py
@@ -327,7 +327,7 @@ def testFlexLayoutStatsSmall(t, env):
     2) GETDEVINFO
     3) LAYOUTRETURN, CLOSE
 
-    FLAGS: flex
+    FLAGS: flex layoutstats
     CODE: FFLS1
     """
     lats = [93089, 107683, 112340, 113195, 130412, 138390, 140427, 158824, 193078, 201879, 391634, 404757, 2201181, 2232614, 2280089, 2296343, 2341763, 2392984, 3064546, 3070314]
@@ -399,3 +399,196 @@ def testFlexLayoutStatsSmall(t, env):
                op.close(0, open_stateid)]
         res = sess.compound(ops)
         check(res)
+
+def _LayoutStats(t, env, stats):
+    '''Loop over the provided layoutstats, sending them on in time
+    '''
+    sess = env.c1.new_pnfs_client_session(env.testname(t))
+
+    # Create the file
+    res = create_file(sess, env.testname(t))
+    check(res)
+    fh = res.resarray[-1].object
+    open_stateid = res.resarray[-2].stateid
+    lo_stateid = open_stateid
+
+    ops = [op.putfh(fh),
+           op.layoutget(False, LAYOUT4_FLEX_FILES,
+                        LAYOUTIOMODE4_RW,
+                        0, 0xffffffffffffffff, 8192, lo_stateid, 0xffff)]
+    res = sess.compound(ops)
+    check(res)
+    lo_stateid = res.resarray[-1].logr_stateid
+    check_seqid(lo_stateid, 1)
+
+    layout = res.resarray[-1].logr_layout[-1]
+    p = FlexUnpacker(layout.loc_body)
+    opaque = p.unpack_ff_layout4()
+    p.done()
+
+    stats_hint = opaque.ffl_stats_collect_hint
+
+    # Assume one mirror/storage device
+    ds = opaque.ffl_mirrors[-1].ffm_data_servers[-1]
+
+    deviceid = ds.ffds_deviceid
+
+    ops = [op.putfh(fh),
+           op.getdeviceinfo(deviceid, LAYOUT4_FLEX_FILES, 0xffffffff, 0)]
+    res = sess.compound(ops)
+    check(res)
+
+    gda = res.resarray[-1].gdir_device_addr
+
+    p = FlexUnpacker(gda.da_addr_body)
+    da = p.unpack_ff_device_addr4()
+    p.done()
+
+    rd_io = io_info4()
+    wr_io = io_info4()
+
+    rd_lat = ff_io_latency4()
+    wr_lat = ff_io_latency4()
+
+    for s in stats:
+        dur = get_nfstime(s[1])
+
+        # Did not capture these in the gathered traces
+        offset = 0
+        file_length = 0xffffffffffffffff
+        rd_io.ii_count = 0
+        rd_io.ii_bytes = 0
+        wr_io.ii_count = 0
+        wr_io.ii_bytes = 0
+
+        rd_lat.ffil_ops_requested = s[5]
+        rd_lat.ffil_bytes_requested = s[4]
+        rd_lat.ffil_ops_completed = s[6]
+        rd_lat.ffil_bytes_completed = s[2]
+        rd_lat.ffil_bytes_not_delivered = s[3]
+        rd_lat.ffil_total_busy_time = get_nfstime(s[7])
+        rd_lat.ffil_aggregate_completion_time = get_nfstime(s[8])
+        wr_lat.ffil_ops_requested = s[12]
+        wr_lat.ffil_bytes_requested = s[11]
+        wr_lat.ffil_ops_completed = s[13]
+        wr_lat.ffil_bytes_completed = s[9]
+        wr_lat.ffil_bytes_not_delivered = s[10]
+        wr_lat.ffil_total_busy_time = get_nfstime(s[14])
+        wr_lat.ffil_aggregate_completion_time = get_nfstime(s[15])
+
+        sleeper = s[0]
+        env.sleep(sleeper)
+        fflu = ff_layoutupdate4(da.ffda_netaddrs[-1], ds.ffds_fh_vers[-1],
+                                rd_lat, wr_lat, dur, True)
+        p = FlexPacker()
+        p.pack_ff_layoutupdate4(fflu)
+        lu4 = layoutupdate4(LAYOUT4_FLEX_FILES, p.get_buffer())
+
+        ops = [op.putfh(fh),
+               op.layoutstats(offset, file_length, lo_stateid, rd_io, wr_io, deviceid, lu4)]
+        res = sess.compound(ops)
+        check(res)
+
+    ops = [op.putfh(fh),
+           op.layoutreturn(False, LAYOUT4_FLEX_FILES, LAYOUTIOMODE4_ANY,
+                           layoutreturn4(LAYOUTRETURN4_FILE,
+                                         layoutreturn_file4(0, 0xffffffffffffffff, lo_stateid, "")))]
+    res = sess.compound(ops)
+    check(res)
+    res = close_file(sess, fh, stateid=open_stateid)
+    check(res)
+
+def testFlexLayoutStatsReset(t, env):
+    """These layoutstats are from when the client effectively resets them
+    by having one field be less than the cumulative ancestor
+
+    FLAGS: flex layoustats
+    CODE: FFLS2
+    """
+
+    ls = [[15, 14997377109, 756789248, 0, 756834304, 184774, 184763, 14996867426, 135877046309, 252579840, 0, 252665856, 61686, 61665, 14997307909, 336986104593],
+          [15, 29997404625, 1527537664, 0, 1527566336, 372941, 372934, 29996142132, 275416132139, 508502016, 0, 508604416, 124171, 124146, 29997293567, 670368077434],
+          [15, 44999356031, 2331115520, 0, 2331136000, 569125, 569120, 44997516473, 414235887583, 775569408, 0, 775680000, 189375, 189348, 44999096896, 1004056428600],
+          [15, 60001513873, 3142483968, 0, 3142529024, 767219, 767208, 59999263507, 550956049466, 1044996096, 0, 1045082112, 255147, 255126, 60001232968, 1340163285214],
+          [15, 75001564615, 3969384448, 0, 3969413120, 969095, 969088, 74999204445, 687761120289, 1320456192, 0, 1320542208, 322398, 322377, 75001158793, 1676193906267],
+          [15, 90001651970, 4873195520, 0, 4873248768, 1189758, 1189745, 89999194540, 828644696229, 1620467712, 0, 1620545536, 395641, 395622, 90000994588, 2006906488984],
+          [15, 105001710572, 5816430592, 0, 5816467456, 1420036, 1420027, 104995782871, 979226777566, 1935175680, 0, 1935269888, 472478, 472455, 104999171073, 2326727992588],
+          [15, 14997245247, 1466019840, 0, 1466097664, 357934, 357915, 15001797989, 277140995467, 487624704, 0, 487677952, 119062, 119049, 14997939745, 179221181962],
+          [15, 29999503656, 2929393664, 0, 2929500160, 715210, 715184, 30001965158, 554484427501, 974204928, 0, 974229504, 237849, 237843, 29998797328, 359060066193],
+          [15, 45000138417, 4245204992, 0, 4245245952, 1036437, 1036427, 45005641995, 825579118923, 1411981312, 0, 1412071424, 344744, 344722, 44996637179, 547563519532],
+          [15, 60000125536, 5545734144, 0, 5545807872, 1353957, 1353939, 60009284822, 1097378466922, 1844367360, 0, 1844400128, 450293, 450285, 59996684404, 735124264647],
+          [15, 14999894874, 1278164992, 0, 1278226432, 312067, 312052, 15006094174, 270749903934, 425877504, 0, 425947136, 103991, 103974, 15000341906, 189401125380],
+          [15, 30000017314, 2586595328, 0, 2586648576, 631506, 631493, 30009142707, 540229533389, 860536832, 0, 860614656, 210111, 210092, 29999220098, 379353634204],
+          [15, 44999991304, 3859476480, 0, 3859574784, 942279, 942255, 45011969088, 808964878766, 1283543040, 0, 1283575808, 313373, 313365, 44999310875, 571777183394],
+          [15, 60000803942, 5141098496, 0, 5141168128, 1255168, 1255151, 60015665154, 1075012244233, 1709035520, 0, 1709096960, 417260, 417245, 60000142398, 766775808737],
+          [15, 75000722908, 6431453184, 0, 6431526912, 1570197, 1570179, 75018741381, 1344327593333, 2140831744, 0, 2140889088, 522678, 522664, 75000341374, 957762218131],
+          [15, 14990345451, 1310584832, 0, 1310654464, 319984, 319967, 14990338511, 276432361830, 436121600, 0, 436183040, 106490, 106475, 14991353202, 182231098560],
+          [15, 29990415908, 2630619136, 0, 2630701056, 642261, 642241, 29983066936, 554752250256, 875077632, 0, 875126784, 213654, 213642, 29982845793, 362758943732],
+          [15, 44992404751, 3910578176, 0, 3910664192, 954752, 954731, 44982785073, 827471490050, 1300946944, 0, 1300992000, 317625, 317614, 44985003324, 549721947944]]
+
+    _LayoutStats(t, env, ls)
+
+def testFlexLayoutStatsStraight(t, env):
+    """These stats are the same as the reset ones, but have been massaged
+    to keep the server from detecting the reset. I.e., the client
+    has not lost it all!
+
+    FLAGS: flex layoustats
+    CODE: FFLS3
+    """
+
+    ls = [[15, 14997377109, 756789248, 0, 756834304, 184774, 184763, 14996867426, 135877046309, 252579840, 0, 252665856, 61686, 61665, 14997307909, 336986104593],
+          [15, 29997404625, 1527537664, 0, 1527566336, 372941, 372934, 29996142132, 275416132139, 508502016, 0, 508604416, 124171, 124146, 29997293567, 670368077434],
+          [15, 44999356031, 2331115520, 0, 2331136000, 569125, 569120, 44997516473, 414235887583, 775569408, 0, 775680000, 189375, 189348, 44999096896, 1004056428600],
+          [15, 60001513873, 3142483968, 0, 3142529024, 767219, 767208, 59999263507, 550956049466, 1044996096, 0, 1045082112, 255147, 255126, 60001232968, 1340163285214],
+          [15, 75001564615, 3969384448, 0, 3969413120, 969095, 969088, 74999204445, 687761120289, 1320456192, 0, 1320542208, 322398, 322377, 75001158793, 1676193906267],
+          [15, 90001651970, 4873195520, 0, 4873248768, 1189758, 1189745, 89999194540, 828644696229, 1620467712, 0, 1620545536, 395641, 395622, 90000994588, 2006906488984],
+          [15, 105001710572, 5816430592, 0, 5816467456, 1420036, 1420027, 104995782871, 979226777566, 1935175680, 0, 1935269888, 472478, 472455, 104999171073, 2326727992588],
+          [15, 119998955819, 7282450432, 0, 7282565120, 1777970, 1777942, 119997580860, 1256367773033, 2422800384, 0, 2422947840, 591540, 591504, 119997110818, 2505949174550],
+          [15, 135001214228, 8745824256, 0, 8745967616, 2135246, 2135211, 134997748029, 1533711205067, 2909380608, 0, 2909499392, 710327, 710298, 134997968401, 2685788058781],
+          [15, 150001848989, 10061635584, 0, 10061713408, 2456473, 2456454, 150001424866, 1804805896489, 3347156992, 0, 3347341312, 817222, 817177, 149995808252, 2874291512120],
+          [15, 165001836108, 11362164736, 0, 11362275328, 2773993, 2773966, 165005067693, 2076605244488, 3779543040, 0, 3779670016, 922771, 922740, 164995855477, 3061852257235],
+          [15, 180001730982, 12640329728, 0, 12640501760, 3086060, 3086018, 180011161867, 2347355148422, 4205420544, 0, 4205617152, 1026762, 1026714, 179996197383, 3251253382615],
+          [15, 195001853422, 13948760064, 0, 13948923904, 3405499, 3405459, 195014210400, 2616834777877, 4640079872, 0, 4640284672, 1132882, 1132832, 194995075575, 3441205891439],
+          [15, 210001827412, 15221641216, 0, 15221850112, 3716272, 3716221, 210017036781, 2885570123254, 5063086080, 0, 5063245824, 1236144, 1236105, 209995166352, 3633629440629],
+          [15, 225002640050, 16503263232, 0, 16503443456, 4029161, 4029117, 225020732847, 3151617488721, 5488578560, 0, 5488766976, 1340031, 1339985, 224995997875, 3828628065972],
+          [15, 240002559016, 17793617920, 0, 17793802240, 4344190, 4344145, 240023809074, 3420932837821, 5920374784, 0, 5920559104, 1445449, 1445404, 239996196851, 4019614475366],
+          [15, 254992904467, 19104202752, 0, 19104456704, 4664174, 4664112, 255014147585, 3697365199651, 6356496384, 0, 6356742144, 1551939, 1551879, 254987550053, 4201845573926],
+          [15, 269992974924, 20424237056, 0, 20424503296, 4986451, 4986386, 270006876010, 3975685088077, 6795452416, 0, 6795685888, 1659103, 1659046, 269979042644, 4382373419098],
+          [15, 284994963767, 21704196096, 0, 21704466432, 5298942, 5298876, 285006594147, 4248404327871, 7221321728, 0, 7221551104, 1763074, 1763018, 284981200175, 4569336423310]]
+    _LayoutStats(t, env, ls)
+
+def testFlexLayoutStatsOverflow(t, env):
+    """These layoutstats are a write intensive work load in which eventually one stat takes
+    twice longer than the collection period.
+
+    FLAGS: flex layoustats
+    CODE: FFLS4
+    """
+
+    ls = [[27, 27614183359, 0, 0, 0, 0, 0, 0, 0, 41943040, 0, 96468992, 10292, 10240, 26609085208, 134047775590766],
+          [15, 42725368747, 0, 0, 0, 0, 0, 0, 0, 41943040, 0, 2402213888, 15847, 11881, 31458638093, 136367242297571],
+          [15, 57912190475, 0, 0, 0, 0, 0, 0, 0, 41943040, 0, 2406907904, 15924, 11881, 31458638093, 136367242297571],
+          [15, 72921814168, 0, 0, 0, 0, 0, 0, 0, 896532480, 0, 2946293760, 16847, 15969, 70391696445, 275087250172195],
+          [15, 87922239746, 0, 0, 0, 0, 0, 0, 0, 896532480, 0, 3196473344, 18335, 15969, 70391696445, 275087250172195],
+          [15, 102949476399, 0, 0, 0, 0, 0, 0, 0, 1808183296, 0, 4038545408, 20452, 19074, 92455324261, 310159328537298],
+          [15, 117951351182, 0, 0, 0, 0, 0, 0, 0, 2587693056, 0, 4486782976, 22613, 19935, 116950745229, 331739899803911],
+          [16, 133017224561, 0, 0, 0, 0, 0, 0, 0, 2587693056, 0, 4830961664, 23306, 22169, 118004988775, 353778424445917],
+          [15, 148031127154, 0, 0, 0, 0, 0, 0, 0, 4132970496, 0, 5960671232, 29861, 26094, 146128115965, 387064682636158],
+          [15, 163058556237, 0, 0, 0, 0, 0, 0, 0, 5614419968, 0, 7550558208, 40590, 39198, 159139080717, 453635077855389],
+          [15, 178067770476, 0, 0, 0, 0, 0, 0, 0, 5614419968, 0, 7838756864, 41554, 39198, 159139080717, 453635077855389],
+          [15, 193081456711, 0, 0, 0, 0, 0, 0, 0, 6428528640, 0, 8151494656, 43497, 42179, 189486399712, 517147615890054],
+          [15, 208082626131, 0, 0, 0, 0, 0, 0, 0, 7284596736, 0, 8656367616, 47929, 43079, 207082978313, 532741795045495],
+          [15, 223082643294, 0, 0, 0, 0, 0, 0, 0, 7944978432, 0, 9539055616, 58212, 53705, 222083467525, 636168303637199],
+          [15, 238083127306, 0, 0, 0, 0, 0, 0, 0, 7944978432, 0, 9763426304, 62673, 57863, 223491351125, 650450833313121],
+          [15, 253175262253, 0, 0, 0, 0, 0, 0, 0, 7944978432, 0, 9860571136, 65509, 57863, 223491351125, 650450833313121],
+          [15, 268185316876, 0, 0, 0, 0, 0, 0, 0, 8729772032, 0, 10523738112, 71014, 65222, 267165070170, 853839631006322],
+          [17, 285787666679, 0, 0, 0, 0, 0, 0, 0, 9522692096, 0, 10779361280, 72612, 66965, 284787142241, 896650223319399],
+          [33, 318568880195, 0, 0, 0, 0, 0, 0, 0, 9522692096, 0, 10779361280, 72613, 72611, 317562885639, 1120229814239633],
+          [15, 333747489171, 0, 0, 0, 0, 0, 0, 0, 10788278272, 0, 10788802560, 74918, 74790, 332233465692, 1121703181284495],
+          [15, 348749618256, 0, 0, 0, 0, 0, 0, 0, 10801360896, 0, 10801885184, 78112, 77984, 347235605251, 1123668237106158],
+          [14, 362014682745, 0, 0, 0, 0, 0, 0, 0, 10812923904, 0, 10814496768, 81191, 80935, 361134569864, 1125289046746198],
+          [15, 377016435231, 0, 0, 0, 0, 0, 0, 0, 10836291584, 0, 10837864448, 86896, 86640, 376136316640, 1127198465086932],
+          [15, 392027464946, 0, 0, 0, 0, 0, 0, 0, 10852364288, 0, 10853937152, 90820, 90564, 391147321463, 1129113173731145],
+          [15, 407034683097, 0, 0, 0, 0, 0, 0, 0, 10864914432, 0, 10866487296, 93884, 93628, 406154554429, 1131023767183211]]
+    _LayoutStats(t, env, ls)
