<div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif"><p style="box-sizing:border-box;margin-bottom:16px;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";font-size:14px;margin-top:0px"><span style="box-sizing:border-box;font-weight:600">Even with clearing the locks (clear all the LDLM locks on the client after the sync and drop caches commands), the stats look just the same as before. </span></p><p style="box-sizing:border-box;margin-top:0px;margin-bottom:16px;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";font-size:14px"><span style="box-sizing:border-box;font-weight:600">For extents_stats, the stats look like these:</span></p><p style="box-sizing:border-box;margin-bottom:16px;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";font-size:14px;margin-top:0px"><span style="box-sizing:border-box;font-weight:600"></span></p><div class="gmail-snippet-clipboard-content gmail-position-relative gmail-overflow-auto" style="box-sizing:border-box;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";overflow:auto;margin-bottom:0px"><pre style="font-size:11.9px;box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;margin-top:0px;margin-bottom:16px;padding:16px;overflow:auto;line-height:1.45;border-radius:6px"><code style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;padding:0px;margin:0px;background:transparent;border-radius:6px;word-break:normal;border:0px;display:inline;overflow:visible;line-height:inherit">llite.hasanfs-ffff882fdc929800.extents_stats=
snapshot_time:         1634138089.122870 (secs.usecs)
                               read       |                write
      extents            calls    % cum%  |          calls    % cum%
   0K -    4K :            450  100  100  |              0    0    0
   4K -    8K :              0    0  100  |              0    0    0
   8K -   16K :              0    0  100  |              0    0    0
  16K -   32K :              0    0  100  |              0    0    0
  32K -   64K :              0    0  100  |              0    0    0
  64K -  128K :              0    0  100  |              0    0    0
 128K -  256K :              0    0  100  |              0    0    0
 256K -  512K :              0    0  100  |              0    0    0
 512K - 1024K :              0    0  100  |              0    0    0
   1M -    2M :              0    0  100  |           1600   46   46
   2M -    4M :              0    0  100  |              0    0   46
   4M -    8M :              0    0  100  |              0    0   46
   8M -   16M :              0    0  100  |              0    0   46
  16M -   32M :              0    0  100  |           1826   53  100</code></pre></div><p style="box-sizing:border-box;margin-bottom:16px;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";font-size:14px;margin-top:0px"><span style="box-sizing:border-box;font-weight:600">If we take a look at the client-side rpc_stats following are observed:</span></p><div class="gmail-snippet-clipboard-content gmail-position-relative gmail-overflow-auto" style="box-sizing:border-box;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";font-size:14px;overflow:auto"><pre style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;margin-top:0px;margin-bottom:16px;padding:16px;overflow:auto;line-height:1.45;border-radius:6px"><code style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;padding:0px;margin:0px;background:transparent;border-radius:6px;word-break:normal;border:0px;display:inline;overflow:visible;line-height:inherit">osc.hasanfs-OST0000-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.38657 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          0   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       3648 100 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |         47   1   1
2:                       0   0   0   |         47   1   2
3:                       0   0   0   |         48   1   3
4:                       0   0   0   |         49   1   5
5:                       0   0   0   |         50   1   6
6:                       0   0   0   |         59   1   8
7:                       0   0   0   |         55   1   9
8:                       0   0   0   |         68   1  11
9:                       0   0   0   |       2209  60  72
10:                      0   0   0   |       1015  27  99
11:                      0   0   0   |          1   0 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         66   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         66   1   3
512:                     0   0   0   |        132   3   7
1024:                    0   0   0   |        264   7  14
2048:                    0   0   0   |        528  14  28
4096:                    0   0   0   |        864  23  52
8192:                    0   0   0   |       1728  47 100
osc.hasanfs-OST0001-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.39942 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                      61  93  93   |          0   0   0
2:                       1   1  95   |          0   0   0
4:                       0   0  95   |          0   0   0
8:                       0   0  95   |          0   0   0
16:                      0   0  95   |          0   0   0
32:                      0   0  95   |          0   0   0
64:                      0   0  95   |          0   0   0
128:                     1   1  96   |          1   0   0
256:                     2   3 100   |       3792  99 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                      63  96  96   |         45   1   1
2:                       2   3 100   |         45   1   2
3:                       0   0 100   |         45   1   3
4:                       0   0 100   |         45   1   4
5:                       0   0 100   |         45   1   5
6:                       0   0 100   |         49   1   7
7:                       0   0 100   |         47   1   8
8:                       0   0 100   |         57   1   9
9:                       0   0 100   |       2235  58  68
10:                      0   0 100   |       1180  31 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       1   1   1   |         69   1   1
1:                       1   1   3   |          0   0   1
2:                       4   6   9   |          0   0   1
4:                       8  12  21   |          0   0   1
8:                      13  20  41   |          0   0   1
16:                     31  47  89   |          0   0   1
32:                      7  10 100   |          0   0   1
64:                      0   0 100   |          0   0   1
128:                     0   0 100   |          0   0   1
256:                     0   0 100   |         69   1   3
512:                     0   0 100   |        139   3   7
1024:                    0   0 100   |        276   7  14
2048:                    0   0 100   |        552  14  29
4096:                    0   0 100   |        896  23  52
8192:                    0   0 100   |       1792  47 100
osc.hasanfs-OST0002-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.41185 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          0   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       3776 100 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |         43   1   1
2:                       0   0   0   |         45   1   2
3:                       0   0   0   |         46   1   3
4:                       0   0   0   |         46   1   4
5:                       0   0   0   |         47   1   6
6:                       0   0   0   |         48   1   7
7:                       0   0   0   |         48   1   8
8:                       0   0   0   |         53   1   9
9:                       0   0   0   |       2283  60  70
10:                      0   0   0   |       1116  29  99
11:                      0   0   0   |          1   0 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         68   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         68   1   3
512:                     0   0   0   |        136   3   7
1024:                    0   0   0   |        272   7  14
2048:                    0   0   0   |        544  14  28
4096:                    0   0   0   |        896  23  52
8192:                    0   0   0   |       1792  47 100
osc.hasanfs-OST0003-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.42422 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          0   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       4048 100 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |         44   1   1
2:                       0   0   0   |         44   1   2
3:                       0   0   0   |         44   1   3
4:                       0   0   0   |         44   1   4
5:                       0   0   0   |         46   1   5
6:                       0   0   0   |         46   1   6
7:                       0   0   0   |         48   1   7
8:                       0   0   0   |         52   1   9
9:                       0   0   0   |       2487  61  70
10:                      0   0   0   |       1193  29 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         73   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         73   1   3
512:                     0   0   0   |        146   3   7
1024:                    0   0   0   |        292   7  14
2048:                    0   0   0   |        584  14  28
4096:                    0   0   0   |        960  23  52
8192:                    0   0   0   |       1920  47 100
osc.hasanfs-OST0004-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.43647 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          0   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       4048 100 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |         58   1   1
2:                       0   0   0   |         60   1   2
3:                       0   0   0   |         60   1   4
4:                       0   0   0   |         60   1   5
5:                       0   0   0   |         60   1   7
6:                       0   0   0   |         61   1   8
7:                       0   0   0   |         62   1  10
8:                       0   0   0   |         69   1  12
9:                       0   0   0   |       2553  63  75
10:                      0   0   0   |       1005  24 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         73   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         73   1   3
512:                     0   0   0   |        146   3   7
1024:                    0   0   0   |        292   7  14
2048:                    0   0   0   |        584  14  28
4096:                    0   0   0   |        960  23  52
8192:                    0   0   0   |       1920  47 100
osc.hasanfs-OST0005-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.44994 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          0   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       3840 100 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |         38   0   0
2:                       0   0   0   |         38   0   1
3:                       0   0   0   |         38   0   2
4:                       0   0   0   |         38   0   3
5:                       0   0   0   |         38   0   4
6:                       0   0   0   |         39   1   5
7:                       0   0   0   |         39   1   6
8:                       0   0   0   |         47   1   8
9:                       0   0   0   |       2271  59  67
10:                      0   0   0   |       1253  32  99
11:                      0   0   0   |          1   0 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         69   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         69   1   3
512:                     0   0   0   |        138   3   7
1024:                    0   0   0   |        276   7  14
2048:                    0   0   0   |        552  14  28
4096:                    0   0   0   |        912  23  52
8192:                    0   0   0   |       1824  47 100
osc.hasanfs-OST0006-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.46277 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          1   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       4016  99 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |          2   0   0
2:                       0   0   0   |          3   0   0
3:                       0   0   0   |          4   0   0
4:                       0   0   0   |          3   0   0
5:                       0   0   0   |          4   0   0
6:                       0   0   0   |          6   0   0
7:                       0   0   0   |          9   0   0
8:                       0   0   0   |         72   1   2
9:                       0   0   0   |       2083  51  54
10:                      0   0   0   |       1768  44  98
11:                      0   0   0   |         56   1  99
12:                      0   0   0   |          5   0  99
13:                      0   0   0   |          1   0  99
14:                      0   0   0   |          1   0 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         74   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         74   1   3
512:                     0   0   0   |        148   3   7
1024:                    0   0   0   |        296   7  14
2048:                    0   0   0   |        592  14  29
4096:                    0   0   0   |        977  24  53
8192:                    0   0   0   |       1856  46 100
osc.hasanfs-OST0007-osc-ffff882fdc929800.rpc_stats=
snapshot_time:         1634137979.47655 (secs.usecs)
read RPCs in flight:  0
write RPCs in flight: 0
pending write pages:  0
pending read pages:   0

                        read                    write
pages per rpc         rpcs   % cum % |       rpcs   % cum %
1:                       0   0   0   |          0   0   0
2:                       0   0   0   |          0   0   0
4:                       0   0   0   |          0   0   0
8:                       0   0   0   |          0   0   0
16:                      0   0   0   |          0   0   0
32:                      0   0   0   |          0   0   0
64:                      0   0   0   |          0   0   0
128:                     0   0   0   |          0   0   0
256:                     0   0   0   |       3648 100 100

                        read                    write
rpcs in flight        rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |          0   0   0
1:                       0   0   0   |          7   0   0
2:                       0   0   0   |          8   0   0
3:                       0   0   0   |          8   0   0
4:                       0   0   0   |          9   0   0
5:                       0   0   0   |         10   0   1
6:                       0   0   0   |         13   0   1
7:                       0   0   0   |         34   0   2
8:                       0   0   0   |        134   3   6
9:                       0   0   0   |       1929  52  58
10:                      0   0   0   |       1434  39  98
11:                      0   0   0   |         61   1  99
12:                      0   0   0   |          1   0 100

                        read                    write
offset                rpcs   % cum % |       rpcs   % cum %
0:                       0   0   0   |         66   1   1
1:                       0   0   0   |          0   0   1
2:                       0   0   0   |          0   0   1
4:                       0   0   0   |          0   0   1
8:                       0   0   0   |          0   0   1
16:                      0   0   0   |          0   0   1
32:                      0   0   0   |          0   0   1
64:                      0   0   0   |          0   0   1
128:                     0   0   0   |          0   0   1
256:                     0   0   0   |         66   1   3
512:                     0   0   0   |        132   3   7
1024:                    0   0   0   |        264   7  14
2048:                    0   0   0   |        528  14  28
4096:                    0   0   0   |        864  23  52
8192:                    0   0   0   |       1728  47 100</code></pre></div><div class="gmail-snippet-clipboard-content gmail-position-relative gmail-overflow-auto" style="box-sizing:border-box;color:rgb(36,41,47);font-family:-apple-system,system-ui,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";overflow:auto;margin-bottom:0px"><pre style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;margin-top:0px;margin-bottom:16px;padding:16px;overflow:auto;line-height:1.45;border-radius:6px"><code style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;padding:0px;margin:0px;background:transparent;border-radius:6px;word-break:normal;border:0px;display:inline;overflow:visible;line-height:inherit">- Md. Hasanur Rashid</code></pre></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Oct 13, 2021 at 10:40 AM Patrick Farrell <<a href="mailto:pfarrell@ddn.com">pfarrell@ddn.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">




<div dir="ltr">[<strong><font color="red">Caution</font></strong>: Email from External Sender. Do not click or open links or attachments unless you know this sender.]<br><span> </span>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
Interesting!  Usually that would flush the cache, but s<span style="background-color:rgb(255,255,255);display:inline">ometimes drop caches doesn't seem to cause recently written data to be flushed, even after sync.  (There is probably a minor bug
 here.)  But try this:</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
After your sync and drop caches commands, clear all the LDLM locks on the client:</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
lctl set_param ldlm.namespaces.*.lru_size=clear</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
That removes the LDLM locks protecting the data, which should force it out of cache.  Note that locks aren't cleared if there's dirty data, so sync first is essential.</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
-Patrick</div>
<div id="gmail-m_4860994253141422088appendonsend"></div>
<hr style="display:inline-block;width:98%">
<div id="gmail-m_4860994253141422088divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> lustre-discuss <<a href="mailto:lustre-discuss-bounces@lists.lustre.org" target="_blank">lustre-discuss-bounces@lists.lustre.org</a>> on behalf of Md Hasanur Rashid via lustre-discuss <<a href="mailto:lustre-discuss@lists.lustre.org" target="_blank">lustre-discuss@lists.lustre.org</a>><br>
<b>Sent:</b> Wednesday, October 13, 2021 7:36 AM<br>
<b>To:</b> <a href="mailto:lustre-discuss@lists.lustre.org" target="_blank">lustre-discuss@lists.lustre.org</a> <<a href="mailto:lustre-discuss@lists.lustre.org" target="_blank">lustre-discuss@lists.lustre.org</a>><br>
<b>Subject:</b> [lustre-discuss] No read throughput shown for the sequential read write Filebench workload</font>
<div> </div>
</div>
<div>
<div dir="ltr">
<div style="font-family:verdana,sans-serif">Hello Everyone,<br>
<br>
<p style="box-sizing:border-box;margin-bottom:16px;color:rgb(36,41,47);font-size:14px;margin-top:0px">
I am running a Filebench workload which is provided below:</p>
<div style="box-sizing:border-box;color:rgb(36,41,47);font-size:14px;overflow:auto">
<pre style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;margin-top:0px;margin-bottom:16px;padding:16px;overflow:auto;line-height:1.45;border-radius:6px"><code style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;padding:0px;margin:0px;background:transparent;border-radius:6px;word-break:normal;border:0px;display:inline;overflow:visible;line-height:inherit">define fileset name="testF",entries=100,filesize=16m,prealloc,path="/mnt/hasanfs/tmp1"

define process name="readerP",instances=2 {
  thread name="readerT",instances=4 {
  flowop openfile name="openOP",filesetname="testF"
  flowop writewholefile name="writeOP",iters=4,filesetname="testF"
  flowop readwholefile name="readOP",iters=1,filesetname="testF"
  flowop closefile name="closeOP"
  }
}

create files
system "sync"
system "echo 3 > /proc/sys/vm/drop_caches"

run 60
</code></pre>
</div>
<p style="box-sizing:border-box;margin-top:0px;margin-bottom:16px;color:rgb(36,41,47);font-size:14px">
I am running the workload in a Lustre cluster. When I check the log from the server-side, it shows the following (I have provided stats of one OSS):</p>
<div style="box-sizing:border-box;color:rgb(36,41,47);font-size:14px;overflow:auto">
<pre style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;margin-top:0px;margin-bottom:16px;padding:16px;overflow:auto;line-height:1.45;border-radius:6px"><code style="box-sizing:border-box;font-family:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;font-size:11.9px;padding:0px;margin:0px;background:transparent;border-radius:6px;word-break:normal;border:0px;display:inline;overflow:visible;line-height:inherit">obdfilter.hasanfs-OST0000.stats=
snapshot_time             1633361244.519122 secs.usecs
read_bytes                1 samples [bytes] 4096 4096 4096
write_bytes               8479 samples [bytes] 1048576 1048576 8890875904
destroy                   13 samples [reqs]
statfs                    76 samples [reqs]
preprw                    8480 samples [reqs]
commitrw                  8480 samples [reqs]
ping                      57 samples [reqs]

obdfilter.hasanfs-OST0000.brw_stats=
snapshot_time:         1633361244.519588 (secs.usecs)

                           read      |     write
pages per bulk r/w     rpcs  % cum % |  rpcs        % cum %
256:                     0   0   0   | 8479 100 100

                           read      |     write
discontiguous pages    rpcs  % cum % |  rpcs        % cum %
0:                       0   0   0   | 8479 100 100

                           read      |     write
discontiguous blocks   rpcs  % cum % |  rpcs        % cum %
0:                       0   0   0   | 8479 100 100

                           read      |     write
disk fragmented I/Os   ios   % cum % |  ios         % cum %
1:                       0   0   0   | 7499  88  88
2:                       0   0   0   |  980  11 100

                           read      |     write
disk I/Os in flight    ios   % cum % |  ios         % cum %
1:                       0   0   0   | 7921  83  83
2:                       0   0   0   | 1407  14  98
3:                       0   0   0   |  116   1  99
4:                       0   0   0   |   15   0 100

                           read      |     write
I/O time (1/1000s)     ios   % cum % |  ios         % cum %
2:                       0   0   0   | 1963  23  23
4:                       0   0   0   | 5627  66  89
8:                       0   0   0   |  837   9  99
16:                      0   0   0   |   25   0  99
32:                      0   0   0   |   27   0 100

                           read      |     write
disk I/O size          ios   % cum % |  ios         % cum %
4K:                      0   0   0   |   62   0   0
8K:                      0   0   0   |  127   1   1
16K:                     0   0   0   |  113   1   3
32K:                     0   0   0   |    0   0   3
64K:                     0   0   0   |    0   0   3
128K:                    0   0   0   |   65   0   3
256K:                    0   0   0   |    0   0   3
512K:                    0   0   0   | 1127  11  15
1M:                      0   0   0   | 7965  84 100
</code></pre>
</div>
<p style="box-sizing:border-box;margin-top:0px;color:rgb(36,41,47);font-size:14px;margin-bottom:0px">
<span style="box-sizing:border-box"><b>Can anyone please explain to me why I am not seeing any read operations in the stats?</b><br>
<br>
Thanks,<br>
Md. Hasanur Rashid</span></p>
</div>
</div>
</div>
</div>

</blockquote></div>