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	<title>Comments on: 6 terabytes in a Mac Pro</title>
	<atom:link href="http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/feed/" rel="self" type="application/rss+xml" />
	<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/</link>
	<description>Eric Cheng's Journal</description>
	<pubDate>Sat, 22 Nov 2008 00:40:54 +0000</pubDate>
	<generator>http://wordpress.org/?v=2.6</generator>
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		<title>By: Ryan</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-2479528</link>
		<dc:creator>Ryan</dc:creator>
		<pubDate>Wed, 17 Sep 2008 01:56:11 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-2479528</guid>
		<description>&lt;p&gt;Hey Eric, thanks for the info.  I'm thinking about installing 6 drives in my new mac pro.  Is it still working out for you? Any problems?  Also, I assume you used the odd sata ports for the other drives, correct?  Thanks!&lt;/p&gt;
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		<content:encoded><![CDATA[<p>Hey Eric, thanks for the info.  I&#8217;m thinking about installing 6 drives in my new mac pro.  Is it still working out for you? Any problems?  Also, I assume you used the odd sata ports for the other drives, correct?  Thanks!</p>]]></content:encoded>
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		<title>By: echeng</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-525478</link>
		<dc:creator>echeng</dc:creator>
		<pubDate>Mon, 10 Sep 2007 21:54:07 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-525478</guid>
		<description>&lt;p&gt;Hey, Chris!  It was a pain in the ass, and involved needle-nose pliers.  It is &lt;em&gt;way&lt;/em&gt; harder than it should be.&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>Hey, Chris!  It was a pain in the ass, and involved needle-nose pliers.  It is <em>way</em> harder than it should be.</p>]]></content:encoded>
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		<title>By: Chris Emura</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-525083</link>
		<dc:creator>Chris Emura</dc:creator>
		<pubDate>Mon, 10 Sep 2007 07:34:54 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-525083</guid>
		<description>&lt;p&gt;Good lord!  How did you hook up the eSATA cables without removing the plastic (fan) assembly?&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>Good lord!  How did you hook up the eSATA cables without removing the plastic (fan) assembly?</p>]]></content:encoded>
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		<title>By: g d gustafsson</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-509656</link>
		<dc:creator>g d gustafsson</dc:creator>
		<pubDate>Fri, 31 Aug 2007 18:10:49 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-509656</guid>
		<description>&lt;p&gt;RAID 1+0 is a good choice for your work.  Most of your I/O are sequential.  This will allow especially faster read I/O. Entire stripes will be able to be read in parallel using either copy of each chunk. At some point, you may want to think about going to a low cost SAN.  This would be easier in a Windows environment as they now have relatively low cost "SAN in a Box"&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>RAID 1+0 is a good choice for your work.  Most of your I/O are sequential.  This will allow especially faster read I/O. Entire stripes will be able to be read in parallel using either copy of each chunk. At some point, you may want to think about going to a low cost SAN.  This would be easier in a Windows environment as they now have relatively low cost &#8220;SAN in a Box&#8221;</p>]]></content:encoded>
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	<item>
		<title>By: 6 Terabytes (TB) of Storage in a Mac Pro. Jealous Much? &#171; Psychohistory</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507868</link>
		<dc:creator>6 Terabytes (TB) of Storage in a Mac Pro. Jealous Much? &#171; Psychohistory</dc:creator>
		<pubDate>Fri, 31 Aug 2007 06:10:39 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507868</guid>
		<description>&lt;p&gt;[...] the full article, with benchmarks, click here. If you want to buy some prints of his more famous photos, go to his new web gallery.   Posted in [...]&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>[...] the full article, with benchmarks, click here. If you want to buy some prints of his more famous photos, go to his new web gallery.   Posted in [...]</p>]]></content:encoded>
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		<title>By: echeng</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507548</link>
		<dc:creator>echeng</dc:creator>
		<pubDate>Fri, 31 Aug 2007 01:09:16 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507548</guid>
		<description>&lt;p&gt;Chris - Thanks for your input.  I'll send you some data when I'm actually around for a full week and have been cranking away on images!&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>Chris - Thanks for your input.  I&#8217;ll send you some data when I&#8217;m actually around for a full week and have been cranking away on images!</p>]]></content:encoded>
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		<title>By: Chris Emura</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507514</link>
		<dc:creator>Chris Emura</dc:creator>
		<pubDate>Fri, 31 Aug 2007 00:49:05 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507514</guid>
		<description>&lt;p&gt;UERs for HDDs have been flat for many years now and in the field, even for Enterprise class drives (vs. "consumer" level drives, which are one order of magnitude down), they are in the 8-20TB range.  Personally, this is frightening for someone who does a lot of I/O and actually cares about their data.  The proliferation of common formats used for pictures, music, and video tend to mask this VERY well.  "Who cares if a bit or two flips in your abc.mpg file?"&lt;/p&gt;

&lt;p&gt;Other media (flash and optical) which do not have the benefit of Enterprise lineage currently boast even more dismal statistics.&lt;/p&gt;

&lt;p&gt;If things don't start to change, this issue will come to the forefront a bit sooner than most folks realize.  The sky is certainly not falling this year, or next, but given exponential consumption and capability trends....&lt;/p&gt;

&lt;p&gt;Eric, during an "average week" (or whatever your granularity of uptime is), can you send me the amount of "data read" shown by Activity Monitor.  It's a global that doesn't provide per device information, but it's a good way to get a feel for where you currently stand.&lt;/p&gt;

&lt;p&gt;Those of you who do a lot of I/O and do NOT see this as an issue, ask me for the CERN report or simply try it out for yourself.  Create a file with a well known pattern, read it back, repeat.  There are some fine details (throttling your I/O, etc.) but the workload is simple and common. Try it on your favorite media.&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>UERs for HDDs have been flat for many years now and in the field, even for Enterprise class drives (vs. &#8220;consumer&#8221; level drives, which are one order of magnitude down), they are in the 8-20TB range.  Personally, this is frightening for someone who does a lot of I/O and actually cares about their data.  The proliferation of common formats used for pictures, music, and video tend to mask this VERY well.  &#8220;Who cares if a bit or two flips in your abc.mpg file?&#8221;</p>

<p>Other media (flash and optical) which do not have the benefit of Enterprise lineage currently boast even more dismal statistics.</p>

<p>If things don&#8217;t start to change, this issue will come to the forefront a bit sooner than most folks realize.  The sky is certainly not falling this year, or next, but given exponential consumption and capability trends&#8230;.</p>

<p>Eric, during an &#8220;average week&#8221; (or whatever your granularity of uptime is), can you send me the amount of &#8220;data read&#8221; shown by Activity Monitor.  It&#8217;s a global that doesn&#8217;t provide per device information, but it&#8217;s a good way to get a feel for where you currently stand.</p>

<p>Those of you who do a lot of I/O and do NOT see this as an issue, ask me for the CERN report or simply try it out for yourself.  Create a file with a well known pattern, read it back, repeat.  There are some fine details (throttling your I/O, etc.) but the workload is simple and common. Try it on your favorite media.</p>]]></content:encoded>
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		<title>By: Jauder Ho</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507487</link>
		<dc:creator>Jauder Ho</dc:creator>
		<pubDate>Fri, 31 Aug 2007 00:27:43 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507487</guid>
		<description>&lt;p&gt;Ah cool!&lt;/p&gt;

&lt;p&gt;That WiebeTech looks interesting. I would be curious to know how well it works over time. What kind of speeds are you getting writing to it?&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>Ah cool!</p>

<p>That WiebeTech looks interesting. I would be curious to know how well it works over time. What kind of speeds are you getting writing to it?</p>]]></content:encoded>
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		<title>By: Craig Jones</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507463</link>
		<dc:creator>Craig Jones</dc:creator>
		<pubDate>Thu, 30 Aug 2007 23:52:42 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507463</guid>
		<description>&lt;p&gt;I love the 6 drive configuration, I'm doing my own with 750's, but I don't like the Mac Pro Journal suggestions since the author offered no evidence that his configuration actually improved performance at all!&lt;/p&gt;

&lt;p&gt;I'd like to see application benchmarks like FCP once they're configured to properly use the Speed and Data partitions.  I'm not  convinced that the modest and occasional performance benefits of the Speed partition compensate for the hard partitioning and forced seeking that results.  I could easily see overall performance being  degraded; in fact I'd expect it.  "Speed" partitions should be on dedicated, very fast drives.&lt;/p&gt;

&lt;p&gt;I'm disappointed that RAID 10 on OS X doesn't match RAID 0 read speeds.  Perhaps it does and the benchmarks used simply can't show it.  Given sufficient command queuing (not automatic with desktop systems and benchmarks!), identical drive counts should yield similar read speeds for RAID 0 and 1 or 10 unless the programmers are stupid.&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>I love the 6 drive configuration, I&#8217;m doing my own with 750&#8217;s, but I don&#8217;t like the Mac Pro Journal suggestions since the author offered no evidence that his configuration actually improved performance at all!</p>

<p>I&#8217;d like to see application benchmarks like FCP once they&#8217;re configured to properly use the Speed and Data partitions.  I&#8217;m not  convinced that the modest and occasional performance benefits of the Speed partition compensate for the hard partitioning and forced seeking that results.  I could easily see overall performance being  degraded; in fact I&#8217;d expect it.  &#8220;Speed&#8221; partitions should be on dedicated, very fast drives.</p>

<p>I&#8217;m disappointed that RAID 10 on OS X doesn&#8217;t match RAID 0 read speeds.  Perhaps it does and the benchmarks used simply can&#8217;t show it.  Given sufficient command queuing (not automatic with desktop systems and benchmarks!), identical drive counts should yield similar read speeds for RAID 0 and 1 or 10 unless the programmers are stupid.</p>]]></content:encoded>
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		<title>By: echeng</title>
		<link>http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507462</link>
		<dc:creator>echeng</dc:creator>
		<pubDate>Thu, 30 Aug 2007 23:50:21 +0000</pubDate>
		<guid isPermaLink="false">http://echeng.com/journal/2007/08/30/6-terabytes-in-a-mac-pro/#comment-507462</guid>
		<description>&lt;p&gt;Jauder - yes, I do that already. It's part of the reason I bought the RTX400-SV. I can just stick a drive in, fill it up, and move it off-site.&lt;/p&gt;
</description>
		<content:encoded><![CDATA[<p>Jauder - yes, I do that already. It&#8217;s part of the reason I bought the RTX400-SV. I can just stick a drive in, fill it up, and move it off-site.</p>]]></content:encoded>
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