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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">To be precise,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">File size = 64 GB<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Stripe size = 1 GB<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Stripe count = 128<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">But since I have 64 ranks, each rank will write 1 GB on 1 OST till 64 OSTs but what happens to the rest of the 64 OSTs.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Please let me know what happens in this case?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks and Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Prakrati<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Ben Evans [mailto:Ben.Evans@terascala.com]
<br>
<b>Sent:</b> Monday, April 20, 2015 7:24 PM<br>
<b>To:</b> Agrawal, Prakrati PTIN-PTT/ICOE; lustre-discuss@lists.lustre.org<br>
<b>Subject:</b> Re: [lustre-discuss] What happens if my stripe count is set to more than my number of stripes<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black">When you set striping, you set the number of OSTs you would like to use, say for your example, you chose 4.<o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black">The way the file would be striped is that the first GB would be written to OST 1, the second GB would be written to OST 2, etc.<o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black">The 5th GB is written to OST 1 again, etc.<o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black">If you set your stripe size to 128GB, and write 64 GB, you will have written 64GB to OST 1, but nothing to OSTs 2-4.<o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black">I hope this answered your question.<o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black">-Ben Evans<o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:black">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:black"> lustre-discuss <<a href="mailto:lustre-discuss-bounces@lists.lustre.org">lustre-discuss-bounces@lists.lustre.org</a>>
on behalf of <a href="mailto:Prakrati.Agrawal@shell.com">Prakrati.Agrawal@shell.com</a> <<a href="mailto:Prakrati.Agrawal@shell.com">Prakrati.Agrawal@shell.com</a>><br>
<b>Sent:</b> Monday, April 20, 2015 4:47 AM<br>
<b>To:</b> <a href="mailto:lustre-discuss@lists.lustre.org">lustre-discuss@lists.lustre.org</a><br>
<b>Subject:</b> [lustre-discuss] What happens if my stripe count is set to more than my number of stripes</span><span style="font-family:"Calibri","sans-serif";color:#212121">
<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-family:"Calibri","sans-serif";color:#212121"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#212121">Hi,<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#212121"> <o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.5pt;font-family:"Helvetica","sans-serif";color:#222222;background:white">I have a doubt regarding Lustre file system. If I have a file of size 64 GB and I set stripe size to 1GB, my number
of stripes become 64. But if I set my stripe count as 128, what does the Lustre do in that case?</span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#212121"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.5pt;font-family:"Helvetica","sans-serif";color:#222222;background:white"> </span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#212121"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.5pt;font-family:"Helvetica","sans-serif";color:#222222;background:white">Thanks and Regards,</span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#212121"><o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-size:11.5pt;font-family:"Helvetica","sans-serif";color:#222222;background:white">Prakrati</span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#212121"><o:p></o:p></span></p>
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