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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>The checksums don't take up much
space. I'm not in front of a system right now, but if you're looking at a
parity based setup (raidz/z2) you can assume it's going to be similar to raid
5/6 (respectively). Mirrored stripes will be similar to raid10.
Obviously there is the checksum data, but when you're talking TB of data, that
overhead is relatively insignificant. I've got some additional
suggestions for the optimal config if you want to contact me off-list. It
might cost you a new DSL modem though ;)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>-Matt<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> cialug-bounces@cialug.org
[mailto:cialug-bounces@cialug.org] <b><span style='font-weight:bold'>On Behalf
Of </span></b>Dave Weis<br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, September 28,
2011 8:47 AM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">Central
Iowa Linux Users Group</st1:PersonName><br>
<b><span style='font-weight:bold'>Subject:</span></b> [Cialug] ZFS Storage
overhead</span></font><font size=3 face="Times New Roman"><span
style='font-size:12.0pt;font-family:"Times New Roman"'><o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Calibri><span style='font-size:11.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Calibri><span style='font-size:11.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Calibri><span style='font-size:11.0pt'>Is
there a way to calculate overhead vs usable storage for ZFS on Nexenta? For
example, if we had 8 2TB drives and wanted redundancy, how much usable space
will be left when we’re done?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Calibri><span style='font-size:11.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Calibri><span style='font-size:11.0pt'>Dave<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Calibri><span style='font-size:11.0pt'><o:p> </o:p></span></font></p>
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