Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Andrei Borzenkov
14.08.2016 19:20, Chris Murphy пишет: > > As an aside, I'm finding the size information for the data chunk in > 'fi us' confusing... > > The sample file system contains one file: > [root@f24s ~]# ls -lh /mnt/0 > total 1.4G > -rw-r--r--. 1 root root 1.4G Aug 13 19:24 >

Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Wolfgang Mader
On Sunday, August 14, 2016 8:04:14 PM CEST you wrote: > On Sunday, August 14, 2016 10:20:39 AM CEST you wrote: > > On Sat, Aug 13, 2016 at 9:39 AM, Wolfgang Mader > > > > wrote: > > > Hi, > > > > > > I have two questions > > > > > > 1) Layout of raid10 in btrfs >

Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Andrei Borzenkov
14.08.2016 19:20, Chris Murphy пишет: ... > > This volume now has about a dozen chunks created by kernel code, and > the stripe X to devid Y mapping is identical. Using dd and hexdump, > I'm finding that stripe 0 and 1 are mirrored pairs, they contain > identical information. And stripe 2 and 3

Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Wolfgang Mader
On Sunday, August 14, 2016 10:20:39 AM CEST you wrote: > On Sat, Aug 13, 2016 at 9:39 AM, Wolfgang Mader > > wrote: > > Hi, > > > > I have two questions > > > > 1) Layout of raid10 in btrfs > > btrfs pools all devices and than stripes and mirrors across this pool.

Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Chris Murphy
On Sat, Aug 13, 2016 at 9:39 AM, Wolfgang Mader wrote: > Hi, > > I have two questions > > 1) Layout of raid10 in btrfs > btrfs pools all devices and than stripes and mirrors across this pool. Is it > therefore correct, that a raid10 layout consisting of 4 devices

Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Hugo Mills
On Sat, Aug 13, 2016 at 05:39:18PM +0200, Wolfgang Mader wrote: > Hi, > > I have two questions > > 1) Layout of raid10 in btrfs > btrfs pools all devices and than stripes and mirrors across this pool. Is it > therefore correct, that a raid10 layout consisting of 4 devices a,b,c,d is > _not_ >

Re: Likelihood of read error, recover device failure raid10

2016-08-14 Thread Duncan
Wolfgang Mader posted on Sat, 13 Aug 2016 17:39:18 +0200 as excerpted: > Hi, > > I have two questions > > 1) Layout of raid10 in btrfs btrfs pools all devices and than stripes > and mirrors across this pool. Is it therefore correct, that a raid10 > layout consisting of 4 devices a,b,c,d is

Likelihood of read error, recover device failure raid10

2016-08-13 Thread Wolfgang Mader
Hi, I have two questions 1) Layout of raid10 in btrfs btrfs pools all devices and than stripes and mirrors across this pool. Is it therefore correct, that a raid10 layout consisting of 4 devices a,b,c,d is _not_ raid0 |---| - |a|