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<div>Hello,</div>
<div>I'm using mmperfmon to get writing stats on NSD during a write activity on a GPFS filesystem (Lenovo system with dss-g-2.0a).</div>
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<div>I use this command:</div>
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<div># mmperfmon query 'sf-dssio-1.psi.ch|GPFSNSDFS|RAW|gpfs_nsdfs_bytes_written' --number-buckets 48 -b 1<br>
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<div>to get the stats. What it returns is a list of valid values followed by a longer list of 'null' as shown below:<br>
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Legend:<br>
1: sf-dssio-1.psi.ch|GPFSNSDFS|RAW|gpfs_nsdfs_bytes_written<br>
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Row Timestamp gpfs_nsdfs_bytes_written <br>
1 2018-11-15-16:15:57 746586112 <br>
2 2018-11-15-16:15:58 704643072 <br>
3 2018-11-15-16:15:59 805306368 <br>
4 2018-11-15-16:16:00 754974720 <br>
5 2018-11-15-16:16:01 754974720 <br>
6 2018-11-15-16:16:02 763363328 <br>
7 2018-11-15-16:16:03 746586112 <br>
8 2018-11-15-16:16:04 746848256 <br>
9 2018-11-15-16:16:05 780140544 <br>
10 2018-11-15-16:16:06 679923712 <br>
11 2018-11-15-16:16:07 746618880 <br>
12 2018-11-15-16:16:08 780140544 <br>
13 2018-11-15-16:16:09 746586112 <br>
14 2018-11-15-16:16:10 763363328 <br>
15 2018-11-15-16:16:11 780173312 <br>
16 2018-11-15-16:16:12 721420288 <br>
17 2018-11-15-16:16:13 796917760 <br>
18 2018-11-15-16:16:14 763363328 <br>
19 2018-11-15-16:16:15 738197504 <br>
20 2018-11-15-16:16:16 738197504 <br>
21 2018-11-15-16:16:17 null <br>
22 2018-11-15-16:16:18 null <br>
23 2018-11-15-16:16:19 null <br>
24 2018-11-15-16:16:20 null <br>
25 2018-11-15-16:16:21 null <br>
26 2018-11-15-16:16:22 null <br>
27 2018-11-15-16:16:23 null <br>
28 2018-11-15-16:16:24 null <br>
29 2018-11-15-16:16:25 null <br>
30 2018-11-15-16:16:26 null <br>
31 2018-11-15-16:16:27 null <br>
32 2018-11-15-16:16:28 null <br>
33 2018-11-15-16:16:29 null <br>
34 2018-11-15-16:16:30 null <br>
35 2018-11-15-16:16:31 null <br>
36 2018-11-15-16:16:32 null <br>
37 2018-11-15-16:16:33 null <br>
38 2018-11-15-16:16:34 null <br>
39 2018-11-15-16:16:35 null <br>
40 2018-11-15-16:16:36 null <br>
41 2018-11-15-16:16:37 null <br>
42 2018-11-15-16:16:38 null <br>
43 2018-11-15-16:16:39 null <br>
44 2018-11-15-16:16:40 null <br>
45 2018-11-15-16:16:41 null <br>
46 2018-11-15-16:16:42 null <br>
47 2018-11-15-16:16:43 null <br>
48 2018-11-15-16:16:44 null <br>
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<div>If I run again and again I still get the same pattern: valid data (even 0 in case of not write activity) followed by more null data.<br>
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<div>Is that normal ? If not, is there a way to get only non-null data by fine-tuning pmcollector's configuration file ?</div>
<div>The corresponding ZiMon sensor (GPFSNSDFS) have period=1.</div>
<div>The ZiMon version is 4.2.3-7.</div>
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<div>Thanks,</div>
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<div> Alvise<br>
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