<div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:9pt" ><div dir="ltr" >Alvise,</div>
<div dir="ltr" > </div>
<div dir="ltr" >Also note that that DeveloperWorks page was maintained by Scott Faddon. He has since left IBM and that page has unfortunately not been updated for almost 2 years. :-(</div>
<div dir="ltr" > </div>
<div dir="ltr" >This page predates the current version 5.x of SpectrumScale which has been available since the beginning of 2018.</div>
<div dir="ltr" > </div>
<div dir="ltr" >In version 5.x. the statement that there are <em>32 sub-blocks in one block</em> is no longer true.</div>
<div dir="ltr" >Now, by default you get a 4MiB Filesystem blocksize that has 512 sub0clocks, each 8192 bytes long.</div>
<div dir="ltr" ><div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:10.5pt" ><div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:10.5pt" ><div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:10.5pt" ><div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:10.5pt" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div class="socmaildefaultfont" dir="ltr" ><div dir="ltr" style="margin-top: 20px;" ><div style="margin-top: 10px;" ><div style="font-family: sans-serif; font-size: 8pt; margin-bottom: 0.0001pt; line-height: normal;" ><span style="font-size:1.000em;" >Daniel</span></div>
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<div style="margin-bottom: 0.0001pt; line-height: normal;" ><font color="#19A9F3" size="3" style="font-family: "Helvetica Neue", Helvetica, Arial, "Lucida Grande", sans-serif; font-size: 8pt; outline: none;" >_________________________________________________________</font><br style="outline: none;" ><font color="#808080" face="Arial" size="2" ><span style="caret-color: rgb(18, 18, 18);" ><b>Daniel Kidger</b></span></font></div>
<div style="margin-bottom: 0.0001pt; line-height: normal;" ><span style="outline: none; caret-color: rgb(18, 18, 18); color: rgb(18, 18, 18); font-size: 10.666666984558105px;" ><span style="outline: none; font-size: 7.5pt;" >IBM Technical Sales Specialist</span></span></div>
<div style="margin-bottom: 0.0001pt; line-height: normal;" ><span style="outline: none; caret-color: rgb(18, 18, 18); color: rgb(18, 18, 18); font-size: 10.666666984558105px;" ><span style="outline: none; font-size: 7.5pt;" >Spectrum Scale, Spectrum NAS and IBM Cloud Object Store<br style="outline: none;" ><br style="outline: none;" ><span style="font-size:0.857em;" >+</span></span></span><span style="font-size:0.857em;" ><span style="outline: none; font-family: sans-serif; color: rgb(95, 95, 95);" ><span style="outline: none; font-family: Verdana, Geneva, sans-serif;" ><span style="outline: none;" >44-(0)7818 522 266 </span></span></span></span><br style="outline: none; caret-color: rgb(18, 18, 18); color: rgb(18, 18, 18); font-family: sans-serif; font-size: 10.666666984558105px;" ><span style="outline: none; font-family: sans-serif; font-size: 10.666666984558105px; color: rgb(95, 95, 95);" ><span style="outline: none; font-family: Arial, Helvetica, sans-serif;" ><span style="outline: none; font-size: 8pt;" >daniel.kidger@uk.ibm.com</span></span></span>
<table border="0" style="border-collapse:collapse;border-color:#696969;table-layout:fixed;width:264px;word-wrap:break-word;" > <tbody> <tr> <td style="overflow: hidden; width: 88px; border-color : #696969;" ><a href="https://www.youracclaim.com/badges/687cf790-fe65-4a92-b129-d23ae41862ac/public_url" target="_blank"><img alt="" src="https://images.youracclaim.com/images/c49300ae-d13e-4071-90f5-15f59d199c9e/IBM%2BVolunteers%2BGold%2Bv6.png" style="width: 88px; height: 88px;" ></a></td> <td style="overflow: hidden; width: 88px; border-color : #696969;" ><a href="https://www.youracclaim.com/badges/8153c6a7-3e02-40be-87ee-24e27ae9459c/public_url" target="_blank"><img alt="" src="https://images.youracclaim.com/images/f2539224-f951-46b4-b376-b88f21c2be98/IBM-Selling-Certification---Level-1.png" style="width: 88px; height: 88px;" ></a></td> <td style="overflow: hidden; width: 88px; border-color : #696969;" ><a href="https://www.youracclaim.com/badges/78197e2c-4277-4ec9-808b-ad6abe1e1b16/public_url" target="_blank"><img alt="" src="https://images.youracclaim.com/images/ea52b12f-97ac-4e72-8d24-b0ced8054e7d/Storage%2BTechnical%2BV1.png" style="width: 88px; height: 88px;" ></a></td> </tr> </tbody></table>
<div> </div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
<div dir="ltr" > </div>
<div dir="ltr" > </div>
<blockquote data-history-content-modified="1" dir="ltr" style="border-left:solid #aaaaaa 2px; margin-left:5px; padding-left:5px; direction:ltr; margin-right:0px" >----- Original message -----<br>From: david_johnson@brown.edu<br>Sent by: gpfsug-discuss-bounces@spectrumscale.org<br>To: gpfsug main discussion list <gpfsug-discuss@spectrumscale.org><br>Cc:<br>Subject: Re: [gpfsug-discuss] Clarification about blocksize in stardanrd gpfs and GNR<br>Date: Thu, Mar 21, 2019 1:32 PM<br> <br><!--Notes ACF
<meta http-equiv="content-type" content="text/html; charset=utf8" >-->The underlying device in this context is the NSD, network storage device. This has relation at all to 512 byte or 4K disk blocks. Usually around a meg, always a power of two. <br>
<div dir="ltr" id="AppleMailSignature" > -- ddj
<div>Dave Johnson</div></div>
<div dir="ltr" ><br>On Mar 21, 2019, at 9:22 AM, Dorigo Alvise (PSI) <<a href="mailto:alvise.dorigo@psi.ch" target="_blank">alvise.dorigo@psi.ch</a>> wrote:<br> </div>
<blockquote type="cite" ><div dir="ltr" ><!--Notes ACF
<meta http-equiv="Content-Type" content="text/html; charset=utf8" >-->
<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;" ><div>Hi,</div>
<div>I'm a little bit puzzled about different meanings of blocksize for different GPFS installation (standard and gnr).</div>
<div> </div>
<div>From this page <a href="https://www.ibm.com/developerworks/community/wikis/home?lang=en#!/wiki/General%20Parallel%20File%20System%20(GPFS)/page/File%20System%20Planning" target="_blank"> https://www.ibm.com/developerworks/community/wikis/home?lang=en#!/wiki/General%20Parallel%20File%20System%20(GPFS)/page/File%20System%20Planning</a></div>
<div> </div>
<div>I read:</div>
<div><ul> <li><span style="font-size:12px" ><span style="font-family:'arial' , 'helvetica' , sans-serif" >The<span> </span><b>blocksize</b><span> </span>is the largest size IO that GPFS can issue to the underlying device</span></span></li> <li><span style="font-size:12px" ><span style="font-family:'arial' , 'helvetica' , sans-serif" >A<span> </span><b>subblock</b><span> </span>is 1/32nd of blocksize. This is the smallest allocation to a single file</span></span></li></ul>For non-gnr GPFS device is quite clear to me (I hope): it is a single spinning disk (or ssd). And I verified this on a small cluster composed of nsd using their local hard drive.</div>
<div> </div>
<div>Can someone explain what is the "device" in the case of GNR ? a single pdisk ?</div>
<div> </div>
<div>Thanks,</div>
<div> </div>
<div> Alvise
<div> </div></div></div></div></blockquote>
<blockquote type="cite" ><div dir="ltr" ><span>_______________________________________________</span><br><span>gpfsug-discuss mailing list</span><br><span>gpfsug-discuss at <a href="http://spectrumscale.org" target="_blank">spectrumscale.org</a></span><br><span><a href="http://gpfsug.org/mailman/listinfo/gpfsug-discuss" target="_blank">http://gpfsug.org/mailman/listinfo/gpfsug-discuss</a></span></div></blockquote>
<div><font face="Default Monospace,Courier New,Courier,monospace" size="2" >_______________________________________________<br>gpfsug-discuss mailing list<br>gpfsug-discuss at spectrumscale.org<br><a href="http://gpfsug.org/mailman/listinfo/gpfsug-discuss" target="_blank">http://gpfsug.org/mailman/listinfo/gpfsug-discuss</a></font></div></blockquote>
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