<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:taxo="http://purl.org/rss/1.0/modules/taxonomy/" version="2.0">
  <channel>
    <title>topic Why we choose low disk capacity for cache tier when we are using high endurance disks in VMware vSAN Discussions</title>
    <link>https://communities.vmware.com/t5/VMware-vSAN-Discussions/Why-we-choose-low-disk-capacity-for-cache-tier-when-we-are-using/m-p/2950483#M14869</link>
    <description>&lt;P&gt;As I find out there is a direct relation between the size of cache tier and disk's endurance for cache tier according to attach pic when we are using mixed use with DWPD =3 , we have to select large disk capacity 2.4T but when we are using optane ssd as it has DWPD 30&amp;nbsp;&lt;BR /&gt;we can use low capacity 300G . Would you please tell me why we need low disk capacity when we are using high endurance disks ?&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;</description>
    <pubDate>Tue, 24 Jan 2023 15:55:01 GMT</pubDate>
    <dc:creator>baber</dc:creator>
    <dc:date>2023-01-24T15:55:01Z</dc:date>
    <item>
      <title>Why we choose low disk capacity for cache tier when we are using high endurance disks</title>
      <link>https://communities.vmware.com/t5/VMware-vSAN-Discussions/Why-we-choose-low-disk-capacity-for-cache-tier-when-we-are-using/m-p/2950483#M14869</link>
      <description>&lt;P&gt;As I find out there is a direct relation between the size of cache tier and disk's endurance for cache tier according to attach pic when we are using mixed use with DWPD =3 , we have to select large disk capacity 2.4T but when we are using optane ssd as it has DWPD 30&amp;nbsp;&lt;BR /&gt;we can use low capacity 300G . Would you please tell me why we need low disk capacity when we are using high endurance disks ?&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;</description>
      <pubDate>Tue, 24 Jan 2023 15:55:01 GMT</pubDate>
      <guid>https://communities.vmware.com/t5/VMware-vSAN-Discussions/Why-we-choose-low-disk-capacity-for-cache-tier-when-we-are-using/m-p/2950483#M14869</guid>
      <dc:creator>baber</dc:creator>
      <dc:date>2023-01-24T15:55:01Z</dc:date>
    </item>
    <item>
      <title>Re: Why we choose low disk capacity for cache tier when we are using high endurance disks</title>
      <link>https://communities.vmware.com/t5/VMware-vSAN-Discussions/Why-we-choose-low-disk-capacity-for-cache-tier-when-we-are-using/m-p/2950803#M14874</link>
      <description>&lt;P&gt;&lt;a href="https://communities.vmware.com/t5/user/viewprofilepage/user-id/275378"&gt;@baber&lt;/a&gt;&amp;nbsp;, "I find out there is a direct relation between the size of cache tier and disk's endurance for cache tier" - not necessarily, though for any model of SSD/NVMe (e.g. using same flash type) the endurance *should* scale roughly linearly e.g. a 2TB P4600 TLC NVMe may have ~10500 TBW where a 4TB of the same model would be ~21000 TBW. However, this is is not cross-comparable with other models of SSD/NVMe as there is a lot of possible differences including type of NAND memory used, %/TB of over-provisioned cells etc. .&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;"Would you please tell me why we need low disk capacity when we are using high endurance disks ?"&lt;BR /&gt;For example:&lt;BR /&gt;375GB P4800X - 20500 TBW:&lt;BR /&gt;&lt;A href="https://www.vmware.com/resources/compatibility/detail.php?deviceCategory=ssd&amp;amp;productid=42342" target="_blank"&gt;https://www.vmware.com/resources/compatibility/detail.php?deviceCategory=ssd&amp;amp;productid=42342&lt;/A&gt;&lt;BR /&gt;2TB P4600 - 10490 TBW:&lt;BR /&gt;&lt;A href="https://www.vmware.com/resources/compatibility/detail.php?deviceCategory=ssd&amp;amp;productid=41826" target="_blank"&gt;https://www.vmware.com/resources/compatibility/detail.php?deviceCategory=ssd&amp;amp;productid=41826&lt;/A&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;As you can clearly see, both of these devices are rated for vSAN AF Cache-tier and are also Endurance Class D (&amp;gt;=7300 TBW), though you can also see that the above P4800X is less than 1/5th of the size and has 2x the endurance of the above P4600.&lt;/P&gt;</description>
      <pubDate>Wed, 25 Jan 2023 22:55:38 GMT</pubDate>
      <guid>https://communities.vmware.com/t5/VMware-vSAN-Discussions/Why-we-choose-low-disk-capacity-for-cache-tier-when-we-are-using/m-p/2950803#M14874</guid>
      <dc:creator>TheBobkin</dc:creator>
      <dc:date>2023-01-25T22:55:38Z</dc:date>
    </item>
  </channel>
</rss>

