Difference between storage_usage and df -Th output

rupenc

We were trying to use storage_usage view to monitor disk space usage in Vertica nodes. However, we failed to tally the numbers from storage_usage view with the output of df -Th command. So, we became unsure if we are missing anything.

 

The query I used-

select path,device, filesystem, round(used_bytes/power(1024,3),2) as used_GB, usage_percent from storage_usage where node_name='v_db_node0001' order by 2,3

Output of above query-

 

| path | device | filesystem | used_GB | usage_percent |
|         |            | vertica | 221.28 | 5.92 |
| /boot  | /dev/sda1 | ext4 | 0.08 | 32.96 |
| /      | /dev/sda3 | ext4 | 65.47 | 8.41 |
| /vertica/data | /dev/sdb | ext4 | 155.81 | 5.27 |
| /vertica/catalog | /dev/sdc | ext4 | 50.91 | 7.26|
| /dev | udev |devtmpfs | 0.0 | 0.0 |

 

While, output from df -Th looks like below:

Filesystem    Type    Size  Used Avail Use% Mounted on
/dev/sda3     ext4    779G   26G  714G   4% /
tmpfs        tmpfs     64G     0   64G   0% /dev/shm
/dev/sda1     ext4    243M   68M  163M  30% /boot
/dev/sdb      ext4    2.9T  5.7G  2.8T   1% /vertica/data
/dev/sdc      ext4    702G   16G  651G   3% /vertica/catalog

Is there any explanation for this variation?

 

Thanks,

Rupendra