On Wed, 2022-11-09 at 11:05 +0100, didier gaumet wrote: > Le 09/11/2022 à 10:27, hw a écrit : > [...] > > Yes, I've seen those. I can only wonder how much performance impact VDO > > would > > have for backups. And I wonder why it doesn't require as much memory as ZFS > > seems to need for deduplication. > > It's *only* an hypothesis, but I would suppose that ZFS was designed > (originally by Sun, hardware vendor) primarily with performances in > mind,
I don't think it was, see https://docs.freebsd.org/en/books/handbook/zfs/ I does mention performance, but I remember other statements saying that was designed for arrays with 40+ disks and, besides data integrity, with ease of use in mind. Performance doesn't seem paramount. Also see https://wiki.gentoo.org/wiki/ZFS > at the expense of strong hardware needs, while RedHat (primarily > software editor before its acquisition by IBM) designed VDO more with > TCO and integration of already existant customer infrastructure in mind, > at the expense of pure performances. Well, the question is what you mean by performance. Maybe ZFS can deduplicate faster than VDO, but eating tons of RAM and/or having to replace all the hardware may not be a kind of performance one would be looking for.