Thou I’m not a hardcore storage system professional: What disk are you using ? There are two types: 1. SMR managed by device firmware. BTRFS sees that as a normal block device … problems you get are not related to BTRFS it self … 2. SMR managed by host system, BTRFS still does see this as a block device … just emulated by host system to look normal.
In case of funky technologies like that I would research how exactly data is stored in terms of “BAND” and experiment with setting leaf & sector size to match a band, then create a btrfs on this device. Run stress.sh on it for couple of days. If you get errors - setup a two standard disk raid1 btrfs file system run stress.sh to see whenever you get errors on this system - to eliminate possibility that your system is actually generating errors. Then come back and we will see what’s going on :) > On 15 Jul 2016, at 19:29, Hendrik Friedel <hend...@friedels.name> wrote: > > Hello, > > I have a 5TB Seagate drive that uses SMR. > > I was wondering, if BTRFS is usable with this Harddrive technology. So, first > I searched the BTRFS wiki -nothing. Then google. > > * I found this: https://bbs.archlinux.org/viewtopic.php?id=203696 > But this turned out to be an issue not related to BTRFS. > > * Then this: http://www.snia.org/sites/default/files/SDC15_presentations/smr/ > HannesReinecke_Strategies_for_running_unmodified_FS_SMR.pdf > " BTRFS operation matches SMR parameters very closely [...] > > High number of misaligned write accesses ; points to an issue with btrfs > itself > > > * Then this: > http://superuser.com/questions/962257/fastest-linux-filesystem-on-shingled-disks > The BTRFS performance seemed good. > > > * Finally this: http://www.spinics.net/lists/linux-btrfs/msg48072.html > "So you can get mixed results when trying to use the SMR devices but I'd say > it will mostly not work. > But, btrfs has all the fundamental features in place, we'd have to make > adjustments to follow the SMR constraints:" > [...] > I have some notes at > https://github.com/kdave/drafts/blob/master/btrfs/smr-mode.txt"; > > > So, now I am wondering, what the state is today. "We" (I am happy to do that; > but not sure of access rights) should also summarize this in the wiki. > My use-case by the way are back-ups. I am thinking of using some of the > interesting BTRFS features for this (send/receive, deduplication) > > Greetings, > Hendrik > > > --- > Diese E-Mail wurde von Avast Antivirus-Software auf Viren geprüft. > https://www.avast.com/antivirus > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
