<div dir="ltr">Thanks to all for the information. <div><br></div><div>Im happy to say that it is close to what I hoped would be the case. </div><div><br></div><div>Interesting to see the effect of the -n value. Reinforces the need to think about it and not go with the defaults.</div><div><br></div><div>Thanks again,</div><div><br></div><div>Carl.</div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On 7 November 2017 at 03:18, Achim Rehor <span dir="ltr"><<a href="mailto:Achim.Rehor@de.ibm.com" target="_blank">Achim.Rehor@de.ibm.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><font size="2" face="sans-serif">I have no practical experience on these
numbers, however, Peters experience below is matching what i learned from
Dan years ago.</font><br><br><font size="2" face="sans-serif">As long as the -n setting of the FS
(the number of nodes potentially mounting the fs) is more or less matching
the actual number of mounts, </font><br><font size="2" face="sans-serif">this 99.x % before degradation is expected.
If you are far off with that -n estimate, like having it set to 32, but
the actual number of mounts is in the thousands,</font><br><font size="2" face="sans-serif">then degradation happens earlier, since
the distribution of free blocks in the allocation maps is not matching
the actual setup as good as it could be. </font><br><br><font size="2" face="sans-serif">Naturally, this depends also on how
you do filling of the FS. If it is only a small percentage of the nodes,
doing the creates, then the distribution can </font><br><font size="2" face="sans-serif">be 'wrong' as well, and single nodes
run earlier out of allocation map space, and need to look for free blocks
elsewhere, costing RPC cycles and thus performance. </font><br><br><font size="2" face="sans-serif">Putting this in numbers seems quite
difficult ;) </font><br><br><font size="1" face="Arial"><br>Mit freundlichen Grüßen / Kind regards</font><p><font size="2" face="Arial"><b>Achim Rehor</b></font></p><p></p><table width="600" style="border-collapse:collapse"><tbody><tr height="8"><td width="600" colspan="4" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><div align="center"><hr noshade></div></td></tr><tr height="8"><td width="600" colspan="4" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" face="Arial"> </font></td></tr><tr height="8"><td width="496" colspan="3" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" face="Arial">Software
Technical Support Specialist AIX/ Emea HPC Support</font></td><td width="103" rowspan="10" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><div align="right"><img align="bottom" src="cid:_1_D95FF418D95FEE980059980B852581D0" style="border:0px solid"></div></td></tr><tr height="8"><td width="496" colspan="3" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" face="Arial">IBM
Certified Advanced Technical Expert - Power Systems with AIX</font></td></tr><tr height="8"><td width="496" colspan="3" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" face="Arial">TSCC
Software Service, Dept. 7922</font></td></tr><tr height="8"><td width="496" colspan="3" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" face="Arial">Global
Technology Services </font></td></tr><tr height="8"><td width="496" colspan="3" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><div align="center"><hr noshade></div></td></tr><tr height="8"><td width="44" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial">Phone:</font></td><td width="195" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"><a href="tel:+49%207034%202747862" value="+4970342747862" target="_blank">+49-7034-274-7862</a></font></td><td width="257" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> IBM
Deutschland</font></td></tr><tr height="8"><td width="44" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial">E-Mail:</font></td><td width="195" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"><a href="mailto:Achim.Rehor@de.ibm.com" target="_blank">Achim.Rehor@de.ibm.com</a></font></td><td width="257" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> Am
Weiher 24</font></td></tr><tr height="8"><td width="44" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td><td width="195" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td><td width="257" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> 65451
Kelsterbach</font></td></tr><tr height="8"><td width="44" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td><td width="195" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td><td width="257" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> <a href="https://maps.google.com/?q=Am%0D+Weiher+24%C2%A0%C2%A0%C2%A065451%0D+Kelsterbach%C2%A0%C2%A0%C2%A0Germany&entry=gmail&source=g">Germany</a></font></td></tr><tr height="8"><td width="44" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td><td width="195" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td><td width="257" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#0060a0" face="Arial"> </font></td></tr><tr height="8"><td width="600" colspan="4" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><div align="center"><hr noshade></div></td></tr><tr height="8"><td width="600" colspan="4" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" face="Arial"> </font></td></tr><tr height="8"><td width="600" colspan="4" style="border-style:none none none none;border-color:#000000;border-width:0px 0px 0px 0px;padding:0px 0px"><font size="1" color="#a2a2a2" face="Arial">IBM
Deutschland GmbH / Vorsitzender des Aufsichtsrats: Martin Jetter <br>Geschäftsführung: Martina Koederitz (Vorsitzende), Reinhard Reschke, Dieter
Scholz, Gregor Pillen, Ivo Koerner, Christian Noll <br>Sitz der Gesellschaft: Ehningen / Registergericht: Amtsgericht Stuttgart,
HRB 14562 WEEE-Reg.-Nr. DE 99369940 </font></td></tr></tbody></table><br><p><font size="3"> </font><br><br><br><br><font size="1" color="#5f5f5f" face="sans-serif">From:
</font><font size="1" face="sans-serif">Peter Smith <<a href="mailto:peter.smith@framestore.com" target="_blank">peter.smith@framestore.com</a>></font><span class=""><br><font size="1" color="#5f5f5f" face="sans-serif">To:
</font><font size="1" face="sans-serif">gpfsug main discussion
list <<a href="mailto:gpfsug-discuss@spectrumscale.org" target="_blank">gpfsug-discuss@spectrumscale.<wbr>org</a>></font><br></span><font size="1" color="#5f5f5f" face="sans-serif">Date:
</font><font size="1" face="sans-serif">11/06/2017 09:17 AM</font><br><font size="1" color="#5f5f5f" face="sans-serif">Subject:
</font><font size="1" face="sans-serif">Re: [gpfsug-discuss]
Performance of GPFS when filesystem is almost full</font><br><font size="1" color="#5f5f5f" face="sans-serif">Sent by:
</font><font size="1" face="sans-serif"><a href="mailto:gpfsug-discuss-bounces@spectrumscale.org" target="_blank">gpfsug-discuss-bounces@<wbr>spectrumscale.org</a></font><br></p><hr noshade><span class=""><br><br><br><tt><font size="3">Hi Carl.<br></font></tt><br><tt><font size="3">When we commissioned our system we ran an NFS stress
tool, and filled the system to the top.<br></font></tt><br><tt><font size="3">No performance degradation was seen until it was 99.7%
full.<br></font></tt><br><tt><font size="3">I believe that after this point it takes longer to
find free blocks to write to.<br></font></tt><br><tt><font size="3">YMMV.</font></tt><br><br><font size="3">On 6 November 2017 at 03:35, Carl <</font><a href="mailto:mutantllama@gmail.com" target="_blank"><font size="3" color="blue"><u>mutantllama@gmail.com</u></font></a><font size="3">>
wrote:</font><br></span><div><div class="h5"><font size="3">Hi Folk,</font><br><br><font size="3">Does anyone have much experience with the performance
of GPFS as it becomes close to full. In particular I am referring to split
data/meta data, where the data pool goes over 80% utilisation. </font><br><br><font size="3">How much degradation do you see above 80% usage, 90% usage?</font><br><br><font size="3">Cheers,</font><br><br><font size="3">Carl.</font><br><br><br></div></div><span class=""><font size="3"><br>______________________________<wbr>_________________<br>gpfsug-discuss mailing list<br>gpfsug-discuss at </font><a href="http://spectrumscale.org/" target="_blank"><font size="3" color="blue"><u>spectrumscale.org</u></font></a><font size="3" color="blue"><u><br></u></font><a href="http://gpfsug.org/mailman/listinfo/gpfsug-discuss" target="_blank"><font size="3" color="blue"><u>http://gpfsug.org/mailman/<wbr>listinfo/gpfsug-discuss</u></font></a><font size="3"><br></font><br><font size="3"><br><br><br>-- </font><br></span><span class=""><font size="3" color="#4181c0"><b>Peter Smith</b> · Senior Systems Engineer<b><br>London</b> · New York · Los Angeles · Chicago · Montréal</font><font size="3"><br>T <a href="tel:+44%2020%207344%208000" value="+442073448000" target="_blank">+44 (0)20 7344 8000</a> · M </font><a href="tel:+44%20%280%297816%20123009" target="_blank"><font size="3" color="#0082bf">+44
(0)7816 123009</font></a><font size="3"> </font><font size="3" color="#0082bf"><i><br></i></font><a href="https://www.google.co.uk/maps/place/19-23+Wells+Street,+London+W1T+3PQ" target="_blank"><font size="3" color="#0082bf"><i>19-23
Wells Street, London W1T 3PQ</i></font></a><font size="3"> </font><font size="3" color="#0082bf"><br></font><a href="https://twitter.com/framestore" target="_blank"><font size="3" color="#0082bf">Twitter</font></a><font size="3">· </font><a href="https://www.facebook.com/framestore" target="_blank"><font size="3" color="#0082bf">Facebook</font></a><font size="3">· </font><a href="http://www.framestore.com/" target="_blank"><font size="3" color="#0082bf">framestore.com</font></a><font size="3" color="blue"><u><br></u></font><a href="https://www.framestore.com/" target="_blank"></a></span><span class=""><tt><font size="2">______________________________<wbr>_________________<br>gpfsug-discuss mailing list<br>gpfsug-discuss at <a href="http://spectrumscale.org" target="_blank">spectrumscale.org</a><br></font></tt><a href="http://gpfsug.org/mailman/listinfo/gpfsug-discuss" target="_blank"><tt><font size="2">http://gpfsug.org/mailman/<wbr>listinfo/gpfsug-discuss</font></tt></a><tt><font size="2"><br></font></tt><br><br><br></span><p></p><p></p><p></p><br>______________________________<wbr>_________________<br>
gpfsug-discuss mailing list<br>
gpfsug-discuss at <a href="http://spectrumscale.org" rel="noreferrer" target="_blank">spectrumscale.org</a><br>
<a href="http://gpfsug.org/mailman/listinfo/gpfsug-discuss" rel="noreferrer" target="_blank">http://gpfsug.org/mailman/<wbr>listinfo/gpfsug-discuss</a><br>
<br></blockquote></div><br></div>