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John,</div>
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I believe the lfs-setstripe man page is incorrect (or at least misleading) in this case. I recall seeing 2000 hardcoded as a maximum, so it appears to be picking that.</div>
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<span style="font-size: 14.6667px; background-color: rgb(255, 255, 255);">Using "-C -1" to put a single stripe on each OST wouldn't have any benefit over "-c -1".
</span><span style="font-size: 11pt;"> IMHO, it would probably be more useful to have negative values represent number of stripes per OST. 🙂</span></div>
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-Nathan</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> lustre-discuss <lustre-discuss-bounces@lists.lustre.org> on behalf of John Bauer <bauerj@iodoctors.com><br>
<b>Sent:</b> Friday, May 17, 2024 8:48 AM<br>
<b>To:</b> lustre-discuss <lustre-discuss@lists.lustre.org><br>
<b>Subject:</b> [lustre-discuss] Unexpected result with overstriping</font>
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<p>Good morning all,</p>
<p>I am playing around with overstriping a bit and I found a behavior that, to me, would seem unexpected. The documentation for -C -1 indicates that the file should be striped over all available OSTs. The pool, which happens to be the default, is ssd-pool
which has 32 OSTs. I got a stripeCount of 2000. Is this as expected?<font face="Courier New, Courier, monospace"><br>
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<p><font face="Courier New, Courier, monospace">pfe20.jbauer2 213> rm -f /nobackup/jbauer2/ddd.dat<br>
pfe20.jbauer2 214> lfs setstripe -C -1 /nobackup/jbauer2/ddd.dat<br>
pfe20.jbauer2 215> lfs getstripe /nobackup/jbauer2/ddd.dat<br>
/nobackup/jbauer2/ddd.dat<br>
lmm_stripe_count: 2000<br>
lmm_stripe_size: 1048576<br>
lmm_pattern: raid0,overstriped<br>
lmm_layout_gen: 0<br>
lmm_stripe_offset: 119<br>
lmm_pool: ssd-pool<br>
obdidx objid objid group<br>
119 52386287 0x31f59ef 0<br>
123 52347947 0x31ec42b 0<br>
127 52734487 0x324aa17 0<br>
121 52839396 0x32643e4 0<br>
131 52742709 0x324ca35 0<br>
116 52242659 0x31d28e3 0<br>
117 51831125 0x316e155 0<br>
124 52425218 0x31ff202 0<br>
125 52402722 0x31f9a22 0<br>
106 52700581 0x32425a5 0</font></p>
edited for brevity<br>
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