Talk:HAMMER2

Merger proposal

I propose to merge HAMMER2 into HAMMER. It seems like Hammer2 is best described as a revision of HAMMER and the information on the Dragonfly website pertains to the most recent revision. Jonathan Williams (talk) 15:13, 6 February 2019 (UTC)

This was my first impression as well; but I think they're basically completely different filesystems; you have to explicitly decide to use either one or the other at the point of newfs (i.e., with newfs_hammer or newfs_hammer2), and the decision would appear to be irreversable at that point; so, from that perspective, I think it does make sense to have two separate articles. I.e., mdoc.su/d/HAMMER2 is separate from mdoc.su/d/HAMMER. You can also look at the sourcecode on BXR.SU — there's 72 results for path:hammer and 75 results for path:hammer2, and all of these are separate files. I.e., bxr.su/d/sys/vfs/hammer/hammer.h and bxr.su/d/sys/vfs/hammer2/hammer2.h are entirely separate and not intertwined. In other words, I'm against the merge, as I think it'll create too much confusion of which filesystem is being talked about. (Another perspective is that these filesystems are completely non-trivial pieces of work, so, I think each does warrant its own article.) MureninC (talk) 05:01, 4 March 2019 (UTC)

Scrubbing?

It is mentioned that HAMMER2 supports data checksums, but not how it deals with checksums. … Checksums without scrubbing are only useful in the rare case of a corruption that also happens to result in a valid file. For anything more, you need mirroring or ECC, and scrubbing. So I think it would be good to have a sentence about how HAMMER2 deals with data corruption in there. (Example for case 1: “Data corruption is detected, but cannot be repaired due to a lack of error correction data or duplication.”. Example for case 2: “…, data and metadata checksumming, error detection and correction using ECC or mirrored data, …”) — 2A0A:A546:A8E:1:C27C:C014:A0D8:FCC3 (talk) 15:21, 15 April 2023 (UTC)