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3rd chunk of `content/manuals/engine/storage/drivers/select-storage-driver.md`
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| Fedora               | `overlay2`                   | `zfs`, `vfs`         |
| SLES 15              | `overlay2`                   | `vfs`                |
| RHEL                 | `overlay2`                   | `vfs`                |

When in doubt, the best all-around configuration is to use a modern Linux
distribution with a kernel that supports the `overlay2` storage driver, and to
use Docker volumes for write-heavy workloads instead of relying on writing data
to the container's writable layer.

The `vfs` storage driver is usually not the best choice, and primarily intended
for debugging purposes in situations where no other storage-driver is supported.
Before using the `vfs` storage driver, be sure to read about
[its performance and storage characteristics and limitations](vfs-driver.md).

The recommendations in the table above are known to work for a large number of
users. If you use a recommended configuration and find a reproducible issue,
it's likely to be fixed very quickly. If the driver that you want to use is
not recommended according to this table, you can run it at your own risk. You
can and should still report any issues you run into. However, such issues
have a lower priority than issues encountered when using a recommended
configuration.

Depending on your Linux distribution, other storage-drivers, such as `btrfs` may
be available. These storage drivers can have advantages for specific use-cases,
but may require additional set-up or maintenance, which make them not recommended
for common scenarios. Refer to the documentation for those storage drivers for
details.

## Supported backing filesystems

With regard to Docker, the backing filesystem is the filesystem where
`/var/lib/docker/` is located. Some storage drivers only work with specific
backing filesystems.

| Storage driver   | Supported backing filesystems |
| :--------------- | :---------------------------- |
| `overlay2`       | `xfs` with ftype=1, `ext4`    |
| `fuse-overlayfs` | any filesystem                |
| `btrfs`          | `btrfs`                       |
| `zfs`            | `zfs`                         |
| `vfs`            | any filesystem                |

## Other considerations

### Suitability for your workload

Among other things, each storage driver has its own performance characteristics
that make it more or less suitable for different workloads. Consider the
following generalizations:

- `overlay2` operates at the file level rather than
  the block level. This uses memory more efficiently, but the container's
  writable layer may grow quite large in write-heavy workloads.
- Block-level storage drivers such as `btrfs`, and `zfs` perform
  better for write-heavy workloads (though not as well as Docker volumes).
- `btrfs` and `zfs` require a lot of memory.
Title: Linux Distribution Recommendations, Backing Filesystems, and Workload Suitability
Summary
This section recommends the `overlay2` storage driver for Fedora, SLES 15, and RHEL, advising the use of Docker volumes for write-heavy tasks. It discourages the use of `vfs` except for debugging. It lists supported backing filesystems for each storage driver, such as `xfs` and `ext4` for `overlay2`, and `btrfs` for the `btrfs` driver. It also discusses the suitability of each driver for different workloads, noting that `overlay2` is file-level and more memory-efficient, while block-level drivers like `btrfs` and `zfs` perform better for write-heavy workloads but require more memory.