it looks simple if everything stays as its default value. However, we do want to change the stripe unit size and stripe count to achieve possible higher performance. If so, it would be too troublesome to manually do the calculation every time when we want to locate a given offset(and maybe a certain interval). The 'cephfs map' and 'cephfs show_location' can provide good information as we want, but sadly not for ceph-fuse. That's why I ask for a similar tool. ----------------------- Wu Xiangwei Tel : 0571-86760875 2014 UIS 2, TEAM BORE -----邮件原件----- 发件人: Yan, Zheng [mailto:ukernel@xxxxxxxxx] 发送时间: 2015年12月7日 16:44 收件人: wuxiangwei 09660 (RD) 抄送: ceph-devel@xxxxxxxxxxxxxxx; ceph-users@xxxxxxxxxxxxxx 主题: Re: 答复: how to see file object-mappings for cephfuse client On Mon, Dec 7, 2015 at 1:52 PM, Wuxiangwei <wuxiangwei@xxxxxxx> wrote: > Thanks Yan, what if we wanna see some more specific or detailed information? E.g. with cephfs we may run 'cephfs /mnt/a.txt show_location --offset' to find the location of a given offset. > When using default layout, object size is 4M, (offset / 4194304) is subfix of object name. For example. offset 0 is located in object <inode number in hex>.00000000, offset 4194304 is located in object <inode number in hex>.0000001. For fancy layout, please read http://docs.ceph.com/docs/master/dev/file-striping/ > ----------------------- > Wu Xiangwei > Tel : 0571-86760875 > 2014 UIS 2, TEAM BORE > > > -----邮件原件----- > 发件人: Yan, Zheng [mailto:ukernel@xxxxxxxxx] > 发送时间: 2015年12月7日 11:22 > 收件人: wuxiangwei 09660 (RD) > 抄送: ceph-devel@xxxxxxxxxxxxxxx; ceph-users@xxxxxxxxxxxxxx > 主题: Re: how to see file object-mappings for cephfuse client > > On Mon, Dec 7, 2015 at 10:51 AM, Wuxiangwei <wuxiangwei@xxxxxxx> wrote: >> Hi, Everyone >> >> Recently I'm trying to figure out how to use ceph-fuse. If we mount cephfs as the kernel client, there is a 'cephfs' command tool (though it seems to be 'deprecated') with 'map' and 'show_location' commands to show the RADOS objects belonging to a given file. However, it doesn't work well for ceph-fuse, neither can I find a similar tool to see the mappings. Any suggestions? >> Thank you! > > Rados objects for a give inode is in form <inode number in hex>.xxxxxxxx. > > To get a file's layout, you can use getfattr -n ceph.file.layout <file > name> > > To find a given object is stored on which OSDs, you can use command, > ceph osd map <cephfs data pool> <object name> > >> >> >> ----------------------- >> Wu Xiangwei >> Tel : 0571-86760875 >> 2014 UIS 2, TEAM BORE >> >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" >> in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo >> info at http://vger.kernel.org/majordomo-info.html ��.n��������+%������w��{.n����z��u���ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
