Score:1

ZFS does not count memory usage

in flag

I've a zfs pool (raid10) of 4 hdd (2 tb) within my proxmox installation.

Today i tried to overwrite the free memory with zero data on the root partition. Actually i wrote over 12tb without any errors

-rw-r--r-- 1 root root 5,2T 23. Nov 22:40 file1
-rw-r--r-- 1 root root 4,1T 23. Nov 23:01 file2
-rw-r--r-- 1 root root 2,9T 23. Nov 23:29 file3

The space haven't changed at all, and it seems that i'm able to write and write .. forever .. to my disc.

df -h
Dateisystem      Größe Benutzt Verf. Verw% Eingehängt auf
udev               16G       0   16G    0% /dev
tmpfs             3,2G    1,2M  3,2G    1% /run
rpool/ROOT/pve-1  3,6T     14G  3,5T    1% /
tmpfs              16G     46M   16G    1% /dev/shm
tmpfs             5,0M       0  5,0M    0% /run/lock
rpool             3,5T    128K  3,5T    1% /rpool
rpool/ROOT        3,5T    128K  3,5T    1% /rpool/ROOT
rpool/data        3,5T    128K  3,5T    1% /rpool/data
/dev/fuse         128M     32K  128M    1% /etc/pve
tmpfs             3,2G       0  3,2G    0% /run/user/0


zpool list -v
NAME                                                SIZE  ALLOC   FREE  CKPOINT  EXPANDSZ   FRAG    CAP  DEDUP    HEALTH  ALTROOT
rpool                                              3.62T  14.0G  3.61T        -         -     7%     0%  1.00x    ONLINE  -
  mirror                                           1.81T  7.05G  1.81T        -         -     7%  0.37%      -    ONLINE
    ata-HGST_HUS724020ALA640_PN1134P6KR3SVW-part3      -      -      -        -         -      -      -      -    ONLINE
    ata-HGST_HUS724020ALA640_PN1134P6HGRGXN-part3      -      -      -        -         -      -      -      -    ONLINE
  mirror                                           1.81T  6.96G  1.81T        -         -     7%  0.37%      -    ONLINE
    ata-HGST_HUS724020ALA640_PN1134P6HH2TUN-part3      -      -      -        -         -      -      -      -    ONLINE
    ata-HGST_HUS724020ALA640_PN1134P6JJTK4S-part3      -      -      -        -         -      -      -      -    ONLINE


 zpool list
NAME    SIZE  ALLOC   FREE  CKPOINT  EXPANDSZ   FRAG    CAP  DEDUP    HEALTH  ALTROOT
rpool  3.62T  14.0G  3.61T        -         -     7%     0%  1.00x    ONLINE  -

ZfS is new to me, but that's kind of strange at any way. How can I, or the system ever be aware to know wether a source have free space or not? Reboots haven't change a thing.

Sorry for the german within the linux commands.

May anybody explain me this behaivor or is this a bug?

Regards

Score:2
ca flag

You probably have compression enabled, which converted any amount of zeros you wrote to a single, 512 byte-sized file. A simple du -hs file1 should reveal its actual allocated size.

mangohost

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