ZFS A brief article on ZFS check-summing

[Phishfry]

A good brief read on ZFS check-summing:

Checksumming in filesystems, and why ZFS is doing it right

One of the best aspects of ZFS is its reliability. This can be accomplished using a few features like copy-on-write approach and checksumming. Today we will look at how ZFS does checksumming and why it does it the proper way.

oshogbo.vexillium.org

Some spelling errors in the last line.

 

[ralphbsz]

Very brief. Omits lots of details. Like probability of checksum being spoofed (by an active attacker). Or what part of the stack the checksum protects ... the article only talks about disk errors, but today RAM errors and network errors are also significant. How these software checksums interact with hardware checksums (such as T10DIF). The checksum granularity, if the checksums are on entities large than disk blocks (512 or 4096 byte sectors), then they will read to false sharing and inefficiencies. How far up in the stack on can push checksum, why not have the user program create the checksum all the way in its user space, and then carry it along all the way. It's complicated.