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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Hi,<br>
<br>
Suppose you have m MDTs in your filesystem, and create a new directory and set default directory striping using
<br>
<br>
lfs mkdir --count=c --index=k <path> && lfs setdirstripe --default --count=c <path><br>
<br>
Suppose that c < m and m > 2.<br>
<br>
Then you make subdirectories, like<br>
<br>
mkdir <path>/child.{1,2,3,...}<br>
<br>
a) By design, do the child directories have the same starting index as <path>?<br>
b) By design, are the child directories all striped across the same set of MDTs as <path>?<br>
<div><br>
I didn't see that specified one way or the other in the DNE phase 2 high level design document at http://wiki.opensfs.org/DNE_StripedDirectories_HighLevelDesign_wiki_version. If I should look elsewhere, let me know.<br>
<br>
In a test I was doing today, I noticed that neither (a) nor (b) were true in practice. I'm wondering whether that's a bug or a feature. Here's partial output from my test.<br>
<br>
$ lfs mkdir --count=6 --index=2 /p/lustre/faaland1/count6_index2<br>
$ lfs setdirstripe -D --count=6 /p/lustre/faaland1/count6_index2<br>
$ mkdir /p/lustre/faaland1/count6_index2/subdir.{1,2,3,4,5,6,7,8,9,10,11,12,13,14}<br>
$ lfs getdirstripe /p/lustre/faaland1/count6_index2<br>
/p/lustre/faaland1/count6_index2<br>
lmv_stripe_count: 6 lmv_stripe_offset: 2<br>
mdtidx FID[seq:oid:ver]<br>
2 [0x280000400:0x33f3:0x0]<br>
3 [0x2c0000404:0x33f3:0x0]<br>
4 [0x300000402:0x33f2:0x0]<br>
5 [0x340000407:0x33f1:0x0]<br>
6 [0x380000406:0x33f0:0x0]<br>
7 [0x3c0000404:0x33ef:0x0]<br>
/p/lustre/faaland1/count6_index2/subdir.4<br>
lmv_stripe_count: 6 lmv_stripe_offset: 2<br>
mdtidx FID[seq:oid:ver]<br>
2 [0x280000400:0x33f5:0x0]<br>
3 [0x2c0000404:0x33f5:0x0]<br>
4 [0x300000402:0x33f4:0x0]<br>
5 [0x340000407:0x33f3:0x0]<br>
6 [0x380000406:0x33f2:0x0]<br>
7 [0x3c0000404:0x33f1:0x0]<br>
/p/lustre/faaland1/count6_index2/subdir.9<br>
lmv_stripe_count: 6 lmv_stripe_offset: 5<br>
mdtidx FID[seq:oid:ver]<br>
5 [0x340000400:0x37a1:0x0]<br>
6 [0x380000405:0x37a1:0x0]<br>
7 [0x3c0000402:0x37a0:0x0]<br>
8 [0x40000040e:0x379f:0x0]<br>
9 [0x440000403:0x379e:0x0]<br>
0 [0x200000405:0x379d:0x0]<br>
/p/lustre/faaland1/count6_index2/subdir.3<br>
lmv_stripe_count: 6 lmv_stripe_offset: 5<br>
mdtidx FID[seq:oid:ver]<br>
5 [0x340000400:0x37a0:0x0]<br>
6 [0x380000405:0x37a0:0x0]<br>
7 [0x3c0000402:0x379f:0x0]<br>
8 [0x40000040e:0x379e:0x0]<br>
9 [0x440000403:0x379d:0x0]<br>
0 [0x200000405:0x379c:0x0]<br>
/p/lustre/faaland1/count6_index2/subdir.14<br>
lmv_stripe_count: 6 lmv_stripe_offset: 7<br>
mdtidx FID[seq:oid:ver]<br>
7 [0x3c0000400:0x30d4:0x0]<br>
8 [0x400000403:0x30d4:0x0]<br>
9 [0x440000405:0x30d3:0x0]<br>
0 [0x200000407:0x30d2:0x0]<br>
1 [0x240000407:0x30d1:0x0]<br>
2 [0x280000407:0x30d0:0x0]<br>
...<br>
<br>
<br>
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<div style="font-family:Tahoma; font-size:13px">
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<div class="PlainText">Olaf P. Faaland<br>
Livermore Computing<br>
phone : 925-422-2263 </div>
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