Re: Does ssd auto detected work for microSD cards?
On Mon, Sep 03, 2018 at 10:22:42PM -0600, Chris Murphy wrote: > On Mon, Sep 3, 2018 at 7:53 PM, GWB wrote: > > Curious instance here, but perhaps this is the expected behaviour: > > > > mount | grep btrfs > > /dev/sdb3 on / type btrfs (rw,ssd,subvol=@) > > /dev/sdb3 on /home type btrfs (rw,ssd,subvol=@home) > > /dev/sde1 on /media/gwb09/btrfs-32G-MicroSDc type btrfs > > (rw,nosuid,nodev,uhelper=udisks2) > > > > This is on an Ubuntu 14 client. > > > > /dev/sdb is indeed an ssd, a Samsung 850 EVO 500Gig, where Ubuntu runs > > on btrfs root. It appears btrfs did indeed auto detected an ssd > > drive. However: > > > > /dev/sde is a micro SD card (32Gig Samsung) sitting in a USB 3 card > > reader, inserted into a USB 3 card slot. But ssh is not detected. > > > > So is that the expected behavior? > > cat /sys/block/sde/queue/rotational > > That's what Btrfs uses for detection. I'm willing to bet the SD Card > slot is not using the mmc driver, but instead USB and therefore always > treated as a rotational device. The correct rotational/non-rot status should be provided by the block device driver. The btrfs kernel module or the mkfs utility will not try to guess the status by the device name, this does not belong to that layer. So either the device driver is updated or an udev rule could fix that too.
Re: Does ssd auto detected work for microSD cards?
Great, thank you. That would make sense, but I might have to specify something for the mmcblk devices. Here is the terminal output when the MicroSD is inserted to the USB 3 holder: $ mount | grep btrfs $ /dev/sdb3 on / type btrfs (rw,ssd,subvol=@) $ /dev/sdb3 on /home type btrfs (rw,ssd,subvol=@home) $ /dev/sdd1 on /media/gwb09/btrfs-32G-MicroSDc type btrfs (rw,nosuid,nodev,uhelper=udisks2) $ cat /sys/block/sdd/queue/rotational 1 Now the same MicroSD in the SD slot on the computer: $ mount | grep btrfs $ /dev/sdb3 on / type btrfs (rw,ssd,subvol=@) $ /dev/sdb3 on /home type btrfs (rw,ssd,subvol=@home) $ /dev/mmcblk0p1 on /media/gwb09/btrfs-32G-MicroSDc type btrfs (rw,nosuid,nodev,uhelper=udisks2) $ cat /sys/block/mmcblk0/queue/rotational 0 So Ubuntu 14 knows the mmcblk is non-rotational. It also looks as if the block device has a partition table of some sort by the existence of: /sys/block/mmcblk0/mmcblk0p1 I will see what happens after I install Ubuntu 18. I probably specified the mount options for /dev/sdb in /etc/fstab by using a UUID. I'll probably tweak the ssd mounts, using ssd_spread, ssd, etc. at some point. I've been using nilfs2 for this, but it occurs to me that btrfs will have more support on more platforms and on more OS's. There's also a mounting issue for nilfs2 in Ubuntu 14 which prevents the nilfs-clean daemon from starting. I will see if F2FS is in the kernel of the other machines here. No complaints here, just gratitude, for the money, time and effort on the part of tech firms that support and develop btrfs. I think Oracle developed the first blueprints for btrfs, but I might be wrong. Oracle also, of course, caught vast amounts of flak from some of the open source zfs devs for changing the dev model after buying Sun. But I have no idea what parts of Sun would have survived without a buyer. Gordon On Mon, Sep 3, 2018 at 11:22 PM Chris Murphy wrote: > > On Mon, Sep 3, 2018 at 7:53 PM, GWB wrote: > > Curious instance here, but perhaps this is the expected behaviour: > > > > mount | grep btrfs > > /dev/sdb3 on / type btrfs (rw,ssd,subvol=@) > > /dev/sdb3 on /home type btrfs (rw,ssd,subvol=@home) > > /dev/sde1 on /media/gwb09/btrfs-32G-MicroSDc type btrfs > > (rw,nosuid,nodev,uhelper=udisks2) > > > > This is on an Ubuntu 14 client. > > > > /dev/sdb is indeed an ssd, a Samsung 850 EVO 500Gig, where Ubuntu runs > > on btrfs root. It appears btrfs did indeed auto detected an ssd > > drive. However: > > > > /dev/sde is a micro SD card (32Gig Samsung) sitting in a USB 3 card > > reader, inserted into a USB 3 card slot. But ssh is not detected. > > > > So is that the expected behavior? > > cat /sys/block/sde/queue/rotational > > That's what Btrfs uses for detection. I'm willing to bet the SD Card > slot is not using the mmc driver, but instead USB and therefore always > treated as a rotational device. > > > > If not, does it make a difference? > > > > Would it be best to mount an sd card with ssd_spread? > > For the described use case, it probably doesn't make much of a > difference. It sounds like these are fairly large contiguous files, > ZFS send files. > > I think for both SDXC and eMMC, F2FS is probably more applicable > overall than Btrfs due to its reduced wandering trees problem. But > again for your use case it may not matter much. > > > > > Yet another side note: both btrfs and zfs are now "housed" at Oracle > > (and most of java, correct?). > > Not really. The ZFS we care about now is OpenZFS, forked from Oracle's > ZFS. And a bunch of people not related to Oracle do that work. And > Btrfs has a wide assortment of developers: Facebook, SUSE, Fujitsu, > Oracle, and more. > > > -- > Chris Murphy
Re: Does ssd auto detected work for microSD cards?
On Mon, Sep 3, 2018 at 7:53 PM, GWB wrote: > Curious instance here, but perhaps this is the expected behaviour: > > mount | grep btrfs > /dev/sdb3 on / type btrfs (rw,ssd,subvol=@) > /dev/sdb3 on /home type btrfs (rw,ssd,subvol=@home) > /dev/sde1 on /media/gwb09/btrfs-32G-MicroSDc type btrfs > (rw,nosuid,nodev,uhelper=udisks2) > > This is on an Ubuntu 14 client. > > /dev/sdb is indeed an ssd, a Samsung 850 EVO 500Gig, where Ubuntu runs > on btrfs root. It appears btrfs did indeed auto detected an ssd > drive. However: > > /dev/sde is a micro SD card (32Gig Samsung) sitting in a USB 3 card > reader, inserted into a USB 3 card slot. But ssh is not detected. > > So is that the expected behavior? cat /sys/block/sde/queue/rotational That's what Btrfs uses for detection. I'm willing to bet the SD Card slot is not using the mmc driver, but instead USB and therefore always treated as a rotational device. > If not, does it make a difference? > > Would it be best to mount an sd card with ssd_spread? For the described use case, it probably doesn't make much of a difference. It sounds like these are fairly large contiguous files, ZFS send files. I think for both SDXC and eMMC, F2FS is probably more applicable overall than Btrfs due to its reduced wandering trees problem. But again for your use case it may not matter much. > Yet another side note: both btrfs and zfs are now "housed" at Oracle > (and most of java, correct?). Not really. The ZFS we care about now is OpenZFS, forked from Oracle's ZFS. And a bunch of people not related to Oracle do that work. And Btrfs has a wide assortment of developers: Facebook, SUSE, Fujitsu, Oracle, and more. -- Chris Murphy
Does ssd auto detected work for microSD cards?
Curious instance here, but perhaps this is the expected behaviour: mount | grep btrfs /dev/sdb3 on / type btrfs (rw,ssd,subvol=@) /dev/sdb3 on /home type btrfs (rw,ssd,subvol=@home) /dev/sde1 on /media/gwb09/btrfs-32G-MicroSDc type btrfs (rw,nosuid,nodev,uhelper=udisks2) This is on an Ubuntu 14 client. /dev/sdb is indeed an ssd, a Samsung 850 EVO 500Gig, where Ubuntu runs on btrfs root. It appears btrfs did indeed auto detected an ssd drive. However: /dev/sde is a micro SD card (32Gig Samsung) sitting in a USB 3 card reader, inserted into a USB 3 card slot. But ssh is not detected. So is that the expected behavior? If not, does it make a difference? Would it be best to mount an sd card with ssd_spread? The wiki suggests this, but I thought I would check: https://btrfs.wiki.kernel.org/index.php/Manpage/btrfs(5)#MOUNT_OPTIONS I think this is an older btrfs userland tools bundle: btrfs --version Btrfs v3.12 It's whatever is still in the Ubuntu 14 standard (universal?) repository. Here's the tl/dr. This is incidental info, and probably does not affect the question above, or answer. I use btrfs on Ubuntu root, and then zfs for home (lots of data, just shy of 2 TB on this laptop). I snapshot and send the zfs filesystems onto a btrfs formatted sd card, and then use zfs receive for the backup zpools: sudo zfs send -D -v -i 20180830042620u zpb9/home2@20180904005531u > zfs-send-zpb9-home2-20180904005531u (on the sd card, copy to the back up zpools, and then:) zfs receive -v zpf3/BackUpPoolHome < zfs-send-zpb9-home2-20180904005531u No complaints at all about btrfs for the root file system, and apt-btrfs-snapshot works great for rolling back from failed upgrades. My servers are Solaris and Ubuntu, both of which support zfs, as long as I don't upgrade beyond the "dreaded" point of no return for "open source", zpool version 28 and zfs version 5. When one server is upgraded to Ubuntu 18, I will try again to use btrfs on the larger Toshiba Hard Drives (6TB and 8TB, either the x300 NAS or Desktop models). I don't want to try that with Ubuntu 14 given the older userland tools. Many thanks. Please point me to the correct mail list if this is not the right one. Yet another side note: both btrfs and zfs are now "housed" at Oracle (and most of java, correct?). Any chance of Solaris 11 getting btrfs in the kernel? I'm guessing not for Sparc, but it might help x86 Solaris users migrate to Oracle Linux. At this point, I think Ubuntu is the only distribution with a version of both btrfs and zfs in the kernel. But not Oracle. Gordon Bynum
