From a summary by JP...
A quick note on the thin provisioning and volume size.
All block storage in cloud.rc is thin provisioned and will only consume the amount of space that the data placed on the volume consumes.
If you create a volume that is 160GB in size but you have only put a 5GB of data in it then the amount of actual storage consumed by the volume is just 5GB. Tho volumes grow to consume the size of data placed in them.
Generally speaking, however, volume sizes do not shrink. That means if you delete the 5GB of data in the volume then the storage consumed will still be 5GB although you may not "see" your data in it anymore.
The specifics depend heavily on how the volumes space is managed. Typically this is through a file system, so at minimum the volume consumes the amount of space required to host the file system. Again the storage used will reflect the amount of data you copy to the file system. So if you check how full your disk is, that can give you a good idea of how much storage is actually consumed. This will also be a good value for knowing the minimum size volume your image requires.
That being said, if you copied a bunch of files to the volume and then cleaned up by deleting the data you don't need anymore, the real space consumed will be whatever the high water mark was for total storage that sat on that volume.
The way our image build tools typically work to minimize consumed space is to copy out to a new volume the file tree created after the image build is complete. That way you only consume the space needed.
You can then copy the image into any volume that is at least that big.
Put another way
- Volumes have a maximum size, which is what you see in the GUI, usually a "round" number like 100 GB or 160 GB.
- Volumes are thin provisioned, meaning they actually consume less than this amount of storage available on Cloud.rc hardware.
- Immediately after provisioning, volumes increase their actual hardware usage to match how much data is added to the volume.
- Volumes do not decrease their actual hardware usage when data is deleted.
- Volumes have a "high water mark" reflecting past usage and do not decrease below this. Nor do they increase if data "refills" the empty portions of the actual hardware usage.
From a summary by JP...
A quick note on the thin provisioning and volume size.
All block storage in cloud.rc is thin provisioned and will only consume the amount of space that the data placed on the volume consumes.
If you create a volume that is 160GB in size but you have only put a 5GB of data in it then the amount of actual storage consumed by the volume is just 5GB. Tho volumes grow to consume the size of data placed in them.
Generally speaking, however, volume sizes do not shrink. That means if you delete the 5GB of data in the volume then the storage consumed will still be 5GB although you may not "see" your data in it anymore.
The specifics depend heavily on how the volumes space is managed. Typically this is through a file system, so at minimum the volume consumes the amount of space required to host the file system. Again the storage used will reflect the amount of data you copy to the file system. So if you check how full your disk is, that can give you a good idea of how much storage is actually consumed. This will also be a good value for knowing the minimum size volume your image requires.
That being said, if you copied a bunch of files to the volume and then cleaned up by deleting the data you don't need anymore, the real space consumed will be whatever the high water mark was for total storage that sat on that volume.
The way our image build tools typically work to minimize consumed space is to copy out to a new volume the file tree created after the image build is complete. That way you only consume the space needed.
You can then copy the image into any volume that is at least that big.
Put another way