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<p class="MsoNormal"><span style="font-size:11.0pt">All,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">There is an old idea for reducing the data required to describe file striping by using a bitmap to record which OSTs are in use. As best I can tell, this was most recently described here:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><a href="http://wiki.lustre.org/Layout_Enhancement_Solution_Architecture#Compact_Layouts_2">http://wiki.lustre.org/Layout_Enhancement_Solution_Architecture#Compact_Layouts_2</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I’m curious if this has been pursued any further, if there’s a JIRA or other place that might have more info or be tracking the idea. I poked around and didn’t find anything.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">In particular, this comment:<br>
“</span><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white">with enough data that for each OST index set in the bitmap, a corresponding OST object FID may be computed”<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Points at the difficult part of implementing this.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">So, before I get too far considering this problem - Is there more out there somewhere? Hoping to avoid duplicating work!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thanks,<o:p></o:p></span></p>
<ul style="margin-top:0in" type="disc">
<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1"><span style="font-size:11.0pt">Patrick<o:p></o:p></span></li></ul>
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