yes i know, but the most common SSD size is 1.92 , at least here in my country. and the raid i have to upgrade is made with 2tb spinning disks. (i don't have support for nvme on these old servers) Il giorno lun 27 nov 2023 alle ore 00:08 Gandalf Corvotempesta <gandalf.corvotempesta@xxxxxxxxx> ha scritto: > > yes i know, but the most common SSD size is 1.92 , at least here in my country. > > and the raid i have to upgrade is made with 2tb spinning disks. > > (i don't have support for nvme on these old servers) > > Il dom 26 nov 2023, 23:52 Roman Mamedov <rm@xxxxxxxxxxx> ha scritto: >> >> On Sun, 26 Nov 2023 23:22:51 +0100 >> Gandalf Corvotempesta <gandalf.corvotempesta@xxxxxxxxx> wrote: >> >> > Il giorno dom 26 nov 2023 alle ore 13:22 Wols Lists >> > <antlists@xxxxxxxxxxxxxxx> ha scritto: >> > > If you look at what SMR is, it's only relevant to spinning rust. It >> > > relies on the fact that a read head can be much smaller than a write >> > > head, so provided you shingle your writes (hence the name), you can >> > > over-write half the previous track (so saving space) without rendering >> > > the data unreadable. >> > >> > Thank you all. >> > That's what i've thought but better stay safe than sorry so i've asked. >> > >> > In other words WD Red SSD are safe for a RAID, there is no need to change them >> > (as mostly new) in both array (the grow was finished 1 hour ago: 2 WD >> > Gold SATA 3.5 plus 1 WD RED SSD) >> > >> > Slowly, i'll replace all spinning disks with WD Red SSD >> > I'm not a fan of WD, but 2TB disks able to replace a 2TB HDD are very >> > very rare (the 1.92TB, much more common, can't replace a 2TB disk) >> >> There are three grades of capacity that you can get: >> 1) ~1920 000 000 000 bytes >> 2) ~2000 000 000 000 bytes >> 3) ~2048 000 000 000 bytes >> >> Nobody is marketing the 1st variant as "2TB", you will find "1920G" on the >> packaging and datasheets instead. >> >> 2nd one should be able to replace an HDD, unless there's some smaller >> discrepancy in the sizes near the 2 billion byte mark between HDDs and SSDs. A >> reason to use smaller-than-whole-disk partitions for your RAID. >> >> 3rd is not a common sight in SATA SSDs (but still happens), and is nearly >> universal in NVMe. Of about ten "2 TB" NVMe models I've tested, only one had >> 2000, *all* others were 2048. The 2000 one was Netac NV7000. >> >> -- >> With respect, >> Roman
