<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> </head> <body text="#000000" bgcolor="#FFFFFF"> <tt>I have not seen yet how much better dedup2 in Solaris is, </tt><tt> </tt><tt>but the current Open-ZFS implementation has the following problems</tt><tt> </tt><tt> </tt><tt>- You must keep the dedup table in any case in RAM as this is realtime dedup </tt><tt> </tt><tt>otherwise a pool import or snapshot delete can last ages and performance can become unusable slow. </tt><tt> </tt><tt> </tt><tt>- it requires a lot of RAM that you want to use for caching</tt><tt> and performance. </tt><tt>Depending on data we talk about 1-5 GB RAM / TB dedup data</tt><tt> (that is required additionally to your cache demands). </tt><tt> </tt><tt>- while you can enable on a filesystem level it operates on pool level. </tt><tt> </tt><tt>once activated you cannot disable beside a pool destroy. </tt><tt> </tt><tt> </tt><tt>In the end, it may be a good idea but only when you have enough RAM and very high dedup rates </tt><tt>(say >5-10) </tt><tt>that are much better then the compress rate with lz4</tt><tt> </tt><tt> </tt><tt>Mostly the dedup rate is not good enough compared to a larger pool with lz4 dedup </tt><tt> </tt><tt>where you do not need to care about the dedup restrictions</tt><tt>. </tt><tt> </tt><tt>gea</tt><tt> </tt><tt>@napp-it.org</tt><tt> </tt> <div class="moz-cite-prefix">Am 03.05.2018 um 09:22 schrieb Oliver Weinmann: </div> <blockquote type="cite" cite="mid:767138E0D064A148B03FE8EC1E9325A20138E4145F@GEDAEVW01.a.space.corp"> <meta http-equiv="Context-Type" content="text/html; charset=us-ascii"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <div class="WordSection1"> Hi, I always hear people saying don’t use dedup with ZFS. Is that still the case? We use omnios as a VEEAM backup target and I would assume that using dedup would save a lot of disk space. Best Regards, Oliver </div> <img src="cid:part1.AED58351.DF99A9FD@hfg-gmuend.de" class=""> Oliver Weinmann Head of Corporate ICT Telespazio VEGA Deutschland GmbH Europaplatz 5 - 64293 Darmstadt - Germany Ph: +49 (0)6151 8257 744 | Fax: +49 (0)6151 8257 799 <a href="mailto:oliver.weinmann@telespazio-vega.de" moz-do-not-send="true">oliver.weinmann@telespazio-vega.de</a> <a moz-do-not-send="true">www.telespazio-vega.de</a> Registered office/Sitz: Darmstadt, Register court/Registergericht: Darmstadt, HRB 89231; Managing Director/Geschäftsführer: Sigmar Keller <fieldset class="mimeAttachmentHeader"></fieldset> <pre wrap="">_______________________________________________ OmniOS-discuss mailing list <a class="moz-txt-link-abbreviated" href="mailto:OmniOS-discuss@lists.omniti.com">OmniOS-discuss@lists.omniti.com</a> <a class="moz-txt-link-freetext" href="http://lists.omniti.com/mailman/listinfo/omnios-discuss">http://lists.omniti.com/mailman/listinfo/omnios-discuss</a> </pre> </blockquote> </body> </html>