Re: Ceph + Xen - RBD io hang

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

I use Ceph 0.61.8 and Xen 4.2.2 (Debian) in production, and can't use
kernel 3.10.* on dom0, which hang very soon. But it's visible in kernel
logs of the dom0, not the domU.

Anyway, you should probably re-try with kernel 3.9.11 for the dom0 (I
also use 3.10.9 in domU).

Olivier

Le mardi 27 août 2013 à 11:46 +0100, James Dingwall a écrit :
> Hi,
> 
> I am doing some experimentation with Ceph and Xen (on the same host) and 
> I'm experiencing some problems with the rbd device that I'm using as the 
> block device.  My environment is:
> 
> 2 node Ceph 0.67.2 cluster, 4x OSD (btrfs) and 1x mon
> Xen 4.3.0
> Kernel 3.10.9
> 
> The domU I'm trying to build is from the Ubuntu 13.04 desktop release.  
> When I pass through the rbd (format 1 or 2) device as 
> phy:/dev/rbd/rbd/ubuntu-test then the domU has no problems reading data 
> from it, the test I ran was:
> 
> for i in $(seq 0 1023) ; do
>      dd if=/dev/xvda of=/dev/null bs=4k count=1024 skip=$(($i * 4))
> done
> 
> However writing data causes the domU to hang while while i is still in 
> single figures but it doesn't seem consistent about the exact value.
> for i in $(seq 0 1023) ; do
>      dd of=/dev/xvda of=/dev/zero bs=4k count=1024 seek=$(($i * 4))
> done
> 
> eventually the kernel in the domU will print a hung task warning.  I 
> have tried the domU as pv and hvm (with xen_platform_pci = 1 and 0) but 
> have the same behaviour in both cases.  Once this state is triggered on 
> the rbd device then any interaction with it in dom0 will result in the 
> same hang.  I'm assuming that there is some unfavourable interaction 
> between ceph/rbd and blkback but I haven't found anything in the dom0 
> logs so I would like to know if anyone has some suggestions about where 
> to start trying to hunt this down.
> 
> Thanks,
> James
> _______________________________________________
> ceph-users mailing list
> ceph-users@xxxxxxxxxxxxxx
> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
> 

_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com





[Index of Archives]     [Information on CEPH]     [Linux Filesystem Development]     [Ceph Development]     [Ceph Large]     [Ceph Dev]     [Linux USB Development]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [xfs]


  Powered by Linux