Dell PowerFlex 4.6.x Install and Upgrade Guide

Prepare an NVDIMM or SDPM as a DAX (acceleration) device

Prepare a new NVDIMM or SDPM as a DAX or acceleration device before adding it to the SDS in a Linux system.

1. Using SSH, log in to the Linux server.
2. Run this command to create the namespace, and DAX on the new NVDIMM or SDPM. where <x> is 0 or 1. Create the namespace with region0 and then run the same command with region1.

   ndctl create-namespace --mode=devdax --region=region<X> --align=4k

   For example,

   ndctl create-namespace --mode=devdax --region=region1 --align=4k
   {
     "dev":"namespace1.0",
     "mode":"devdax",
     "map":"dev",
     "size":"15.75 GiB (16.91 GB)",
     "uuid":"e47c3ce0-8a98-4256-8fed-ff2bacead155",
     "daxregion":{
       "id":1,
       "size":"15.75 GiB (16.91 GB)",
       "align":4096,
       "devices":[
         {
           "chardev":"dax1.0",
           "size":"15.75 GiB (16.91 GB)"
         }
       ]
     },
     "align":4096
   }
   

3. Run this command again to validate the namespace was created. In this example, you can see namespace1.0 and dax1.0 was created for region1 NVDIMM or SDPM.

   ndctl list --regions --verbose
   {
     "regions":[
       {
         "dev":"region1",
         "size":17179869184,
         "available_size":17179869184,
         "max_available_extent":17179869184,
         "type":"pmem",
         "numa_node":1,
         "iset_id":-4649799281728009192,
         "persistence_domain":"unknown"
       },
     {
       "dev":"namespace1.0",
       "mode":"devdax",
       "map":"dev",
       "size":16909336576,
       "uuid":"e47c3ce0-8a98-4256-8fed-ff2bacead155",
       "chardev":"dax1.0",
       "align":4096
     },
       {
         "dev":"region0",
         "size":17179869184,
         "available_size":0,
         "max_available_extent":0,
         "type":"pmem",
         "numa_node":0,
         "iset_id":4335710697273129127,
         "persistence_domain":"unknown",
         "namespaces":[
           {
             "dev":"namespace0.0",
             "mode":"devdax",
             "map":"dev",
             "size":16909336576,
             "uuid":"265ef925-571d-4a0a-bb96-dca4a3873000",
             "raw_uuid":"ff7b05b9-510e-4604-8329-7f3dccf10300",
             "daxregion":{
               "id":0,
               "size":16909336576,
               "align":4096,
               "devices":[
                 {
                   "chardev":"dax0.0",
                   "size":16909336576
                 }
               ]
             },
             "align":4096,
           }
         ]
       }
   

4. Record the acceleration device name in the NVDIMM or SDPM information table.
5. Find the full acceleration device path:

   	ls -ltr /dev/ | grep dax

   The following output should appear:

   /dev/daxX.X

   For example:

   /dev/dax0.0

6. Record the acceleration device path in the NVDIMM or SDPM information table.