similar to: Problem with raid0

How can I verify the read speed of a btrfs raid0 pair in archlinux.? I assume raid0 means striped activity in a paralleled mode at lease similar to raid0 in mdadm. How can I measure the btrfs read speed since it is copy-on-write which is not the norm in mdadm raid0.? Perhaps I cannot use the same approach in btrfs to determine the performance. Secondly, I see a methodology for raid10 using

I'm trying to work out the kinks of a proprietary, old, and clunky application that runs on CentOS. One of its main problems is that it writes image sequences extremely non-linearly and in several passes, using many CPUs, so the sequences get very fragmented. The obvious solution to this seems to be to use SSDs for its output, and some scripts that will pick up and copy our the sequences

On 11/04/2020 10:21 PM, John Pierce wrote: > is it RAID 0 (striped) or raid1 (mirrored) ?? > > if you wrote on half of a raid0 stripe set, you basically trashed it. > blocks are striped across both drives, so like 16k on the first disk, then > 16k on the 2nd then 16k back on the first, repeat (replace 16k with > whatever your raid stripe size is). > > if its a raid 1

> On Nov 4, 2020, at 9:21 PM, John Pierce <jhn.pierce at gmail.com> wrote: > > is it RAID 0 (striped) or raid1 (mirrored) ?? > > if you wrote on half of a raid0 stripe set, you basically trashed it. > blocks are striped across both drives, so like 16k on the first disk, then > 16k on the 2nd then 16k back on the first, repeat (replace 16k with > whatever your raid

My computer running CentOS 7 is configured to use BIOS RAID0 and has two identical SSDs which are also encrypted. I had a crash the other day and due to a bug in the operating system update, I am unable to boot the system in RAID mode since dracut does not recognize the disks in grub. After modifying the grub command line I am able to boot the system from one of the harddisks after entering the

hi guys, gals do you know if conversion from lvm's raid10 to raid0 is possible? I'm fiddling with --splitmirrors but it gets me nowhere. On "takeover" subject man pages says: "..between striped/raid0 and raid10."" but no details, nowhere I could find documentation, nor a howto. many thanks, L.

Hi, I do have a disk array that is providing striped LUNs to my Solaris box. Hence I''d like to simply concat those LUNs without adding another layer of striping. Is this possibile with ZFS? As far as I understood, if I use zpool create myPool lun-1 lun-2 ... lun-n I will get a RAID0 striping where each data block is split across all "n" LUNs. If that''s

Hello, i recently installed Centos 5 on a new server with a single scsii disk. After the installation, i added 2 additional disks that were once the components of a raid0 array on another server. I get some errors and am unable to start the array the following is an extract from dmesg output: md: Autodetecting RAID arrays. md: could not open unknown-block(8,17). md: could not open

is it RAID 0 (striped) or raid1 (mirrored) ?? if you wrote on half of a raid0 stripe set, you basically trashed it. blocks are striped across both drives, so like 16k on the first disk, then 16k on the 2nd then 16k back on the first, repeat (replace 16k with whatever your raid stripe size is). if its a raid 1 mirror, then either disk by itself has the complete file system on it, so you should be

I noticed that if I have single-device allocation for data in a multi-device btrfs filesystem, a balance operation will convert the data to RAID0. This is true even if ''-d single'' is specified explicitly when creating the filesystem. Then it wants to continue using RAID0 for future data allocations, and I run out of space once there''s no longer two drives with space

Hi, So the case is, now I''ve got a btrfs image file, which is created from a raid0 btrfs fs. And if I run ''btrfs-image -r image_file /dev/sdf'', then I have to mount it with ''degraded'' mode, and that still fails because raid0 requires two disks at least. So any ideas how to make it work? thanks, liubo -- To unsubscribe from this list: send the line

Hello List, we have a running (test) AD samba4 system running successful for several month. We are now trying to add more DCs to the mix and have a proper backup/desaster recovery strategy. Basically I wan't to adapt the samba_backup script found in the sources to backup everything via git into our repository. I understand that the best solution would be to tar everything before commit. In

I just noticed something very strange on one of our Dell PE1750 servers. It is running FreeBSD 4-STABLE on dual CPU's with the embedded Dell Raid controller (amr driver). Attached are 3 disks of 145GB. On a RAID5 logical drive this gives me ~280GB storage. Up until the last reboot (35 days ago) the 'amrcontrol' status utility gave me: Logical drive 0 Stipes blah Size blah

I have two disks that I formatted as btrfs RAID0 on opensuse 11.3. The raid worked well several days until there was a power surge. The system successfully rebooted and the btrfs raid reappeared, but the kernel occasionally threw oops. That was my first experience with oops. After two days, the btrfs raid failed to mount via fstab and when I manually tried to mount it, there was a kernel

On Mon, Feb 16, 2015 at 6:47 AM, Eliezer Croitoru <eliezer at ngtech.co.il> wrote: > I am unsure I understand what you wrote. > "XFS will create multiple AG's across all of those > devices," > Are you comparing md linear/concat to md raid0? and that the upper level XFS > will run on top them? Yes to the first question, I'm not understanding the second

Did something break.. ? we are not reporting raid type after balance. ----------- # btrfs fi df /btrfs Data, RAID0: total=2.00GB, used=2.03MB Data: total=8.00MB, used=0.00 System, RAID0: total=16.00MB, used=4.00KB System: total=4.00MB, used=0.00 Metadata, RAID0: total=2.00GB, used=216.00KB Metadata: total=8.00MB, used=4.00KB # btrfs bal /btrfs Done, had to relocate 5 out of 5 chunks # btrfs fi

The Wiki does not make it clear as to why adding a secondary device defaults to RAID1 metadata and RAID0 data. I bought two SSDs with the intention of doing a BTRFS RAID0 for my root. What is the difference between forcing RAID0 on metadata and data as opposed to the default behavior? Can anyone clarify that? Thank you for your time, Mario -- To unsubscribe from this list: send the line

tl;dr version: 3.0 produces “bio too big” dmesg entries and silently corrupts data in “meta-raid1/data-single” configurations on disks with different max_hw_sectors, where 2.6.38 worked fine. tl;dr side-issue: on-line removal of partitions holding “single” data attempts to create raid0 (rather than single) block groups. If it can''t get enough room for raid0 over all remaining disks, it

If there is no free space, the free space allocator will try to get space from the block group with the degenerated profile. For example, if there is no free space in the RAID1 block groups, the allocator will try to allocate space from the DUP block groups. And besides that, the space reservation has the similar behaviour: if there is no enough space in the space cache to reserve, it will reserve

With the Dell OpenManage question on my mind (and having seen it answered very well), I was reminded of an interesting and a little surprising thing I saw yesterday. I upgraded a PowerEdge 2850 from CentOS4 to Fedora Core 5 (keeping everything updated for GNUradio to run on CentOS 4 became more of a job that it should have) for our pulsar data processing machine (it has a GNUradio Universal