does PCJ support Device-DAX mode?

[JerryYangSH]

I switched from file dax to dev dax mode (by "sudo ndctl create-namespace --mode devdax --map dev -e namespace0.0 -f"). and hit below error.

# Fork: 1 of 1
# Warmup Iteration   1: opening 0 ...Opening heap... Encountered error opening pool. Please check if /dev/dax0.0 exists and accessible.
<forked VM failed with exit code 255>
<stdout last='20 lines'>
Encountered error opening pool. Please check if /dev/dax0.0 exists and accessible.
</stdout>
<stderr last='20 lines'>
</stderr>

My config is :

jerry@u19:~$ ls /dev/dax0.0 -lr
crw-rw-rw- 1 root root 250, 1 Dec 18 08:26 /dev/dax0.0
jerry@u19:~$ ndctl list
[
  {
    "dev":"namespace0.0",
    "mode":"devdax",
    "map":"dev",
    "size":4225761280,
    "uuid":"bee3770d-cfc6-46e4-a254-5ce12c22ef43",
    "chardev":"dax0.0"
  }
]


jerry@u19:~/$ cat config.properties
# HOW-TO
# Two parameters MUST be specified:
# - path: path to persistent memory pool; this could be one of the following:
#   - path to a file acting as the memory pool, possibly in a PMEM-aware file system; e.g. /mnt/mem/persistent_heap
#   - path to a device DAX, e.g. /dev/dax0.0
#   - path to a fused poolset configuration file, e.g. ~/pcj/myobjpool.set
# - size: size of the memory pool; this could be one of the following:
#   - if using a file-based memory pool: set to any desired pool size not exceeding the size of the device the file is on
#   - if using a device DAX or fused poolset: MUST set to 0; the whole device(s) will be used; any other value will result in an error

path=/dev/dax0.0
size=2147483648

[asonje]

Yes PCJ supports Device-DAX mode. When using device dax you must set the 'size' parameter to 0