zfs/raidz: seems like I'm failing with math

[Eugene M. Zheganin]

Hi.

On 16.10.2016 22:06, Alan Somers wrote:
> It's raw size, but the discrepancy is between 1000 and 1024.  Smartctl
> is reporting base 10 size, but zpool is reporting base 1024..
> 960197124096.0*6/1024**4 = 5.24 TB, which is pretty close to what
> zpool says.
Thanks ! It does explain it. But then again, on a pool that has been 
just created, I check the properties of the root dataset (I'm posting 
all the properties, just to display there's no child datasets or data on 
the pool):

===Cut===
# zfs get all gamestop
NAME      PROPERTY              VALUE                      SOURCE
gamestop  type                  filesystem                 -
gamestop  creation              sun oct 16 19:02 2016  -
gamestop  used                  403K                       -
gamestop  available             4,04T                      -
gamestop  referenced            153K                       -
gamestop  compressratio         1.00x                      -
gamestop  mounted               yes                        -
gamestop  quota                 none                       default
gamestop  reservation           none                       default
gamestop  recordsize            128K                       default
gamestop  mountpoint            /gamestop                  default
gamestop  sharenfs              off                        default
gamestop  checksum              on                         default
gamestop  compression           off                        default
gamestop  atime                 on                         default
gamestop  devices               on                         default
gamestop  exec                  on                         default
gamestop  setuid                on                         default
gamestop  readonly              off                        default
gamestop  jailed                off                        default
gamestop  snapdir               hidden                     default
gamestop  aclmode               discard                    default
gamestop  aclinherit            restricted                 default
gamestop  canmount              on                         default
gamestop  xattr                 off                        temporary
gamestop  copies                1                          default
gamestop  version               5                          -
gamestop  utf8only              off                        -
gamestop  normalization         none                       -
gamestop  casesensitivity       sensitive                  -
gamestop  vscan                 off                        default
gamestop  nbmand                off                        default
gamestop  sharesmb              off                        default
gamestop  refquota              none                       default
gamestop  refreservation        none                       default
gamestop  primarycache          all                        default
gamestop  secondarycache        all                        default
gamestop  usedbysnapshots       0                          -
gamestop  usedbydataset         153K                       -
gamestop  usedbychildren        249K                       -
gamestop  usedbyrefreservation  0                          -
gamestop  logbias               latency                    default
gamestop  dedup                 off                        default
gamestop  mlslabel                                         -
gamestop  sync                  standard                   default
gamestop  refcompressratio      1.00x                      -
gamestop  written               153K                       -
gamestop  logicalused           26,5K                      -
gamestop  logicalreferenced     9,50K                      -
gamestop  volmode               default                    default
gamestop  filesystem_limit      none                       default
gamestop  snapshot_limit        none                       default
gamestop  filesystem_count      none                       default
gamestop  snapshot_count        none                       default
gamestop  redundant_metadata    all                        default
===Cut===

Only 4.03T is available. Looks like it's the actual size, since it's zfs 
and not zpool. But 960197124096 bytes * 5 / 1024^4 gives me 4.366 Tb, 
and not the 4.03 T. Where did about 300 gigs go ? I'm really trying to 
understand, not to catch some questionable logic or find errors.

Thanks.
Eugene.