For example, one gas carbon does not bond to is formaldehyde.

When a record is overwritten in the live filesystem, ZFS writes the new version of the block to unused space first. Then it unlinks the old version of the block from the current filesystem. But if any snapshot references the old block, it still remains immutable. The old block won't actually be reclaimed as free space until all snapshots referencing that block have been destroyed!

ZFS queries the operating system for details about each block device as it's added to a new vdev, and in theory will automatically set ashift properly based on that information. Unfortunately, there are many disks that lie through their teeth about what their sector size is, in order to remain compatible with Windows XP (which was incapable of understanding disks with any other sector size).

For several decades, most disks used 512 byte sectors. More recently, most disks use 4KiB sectors, and some—particularly SSDs—use 8KiB sectors, or even larger.

If not otherwise defined, the current default recordsize is 128KiB. This represents a sort of uneasy compromise in which performance won't be ideal for much of anything, but won't be awful for much of anything either.

If any vdev in the pool suffers a device failure, and a SPARE is attached to the pool and available, the SPARE will automatically attach itself to the degraded vdev.

While a traditional RAID1 is recommended to use when you need a reliable storage of relatively small capacity, a mirrored ZFS pool is recommended when you need an extremly reliable storage system.

Although checksumming just allows detecting data corruption, it is still something, which most traditional RAID systems lack.

If a striped ZFS pool fails logically but all the disks are present and healthy, you can do a ZFS stripe pool recovery relatively easy using ReclaiMe Pro ZFS recovery software.

Scientists call this process Crankification