Incorrect numbers with raid configuration

[ghost]

SUMMARY

Disk bandwith is incorrect

ISSUE TYPE

• Bug Report

DSTAT VERSION

Dstat 0.7.3
Written by Dag Wieers <dag@wieers.com>
Homepage at http://dag.wieers.com/home-made/dstat/

Platform posix/linux2
Kernel 4.12.14
Python 2.7.13 (default, Jan 10 2018, 05:58:05)
[GCC 6.4.0]

Terminal type: xterm (color support)
Terminal size: 32 lines, 132 columns

Processors: 4
Pagesize: 4096
Clock ticks per secs: 100

internal:
        aio, cpu, cpu-adv, cpu-use, cpu24, disk, disk24, disk24-old, epoch, fs, int, int24, io, ipc, load, lock, mem, mem-adv,
        net, page, page24, proc, raw, socket, swap, swap-old, sys, tcp, time, udp, unix, vm, vm-adv, zones
/usr/share/dstat:
        battery, battery-remain, condor-queue, cpufreq, dbus, disk-avgqu, disk-avgrq, disk-svctm, disk-tps, disk-util, disk-wait,
        dstat, dstat-cpu, dstat-ctxt, dstat-mem, fan, freespace, fuse, gpfs, gpfs-ops, helloworld, innodb-buffer, innodb-io,
        innodb-ops, lustre, md-status, memcache-hits, mysql-io, mysql-keys, mysql5-cmds, mysql5-conn, mysql5-innodb,
        mysql5-innodb-basic, mysql5-innodb-extra, mysql5-io, mysql5-keys, net-packets, nfs3, nfs3-ops, nfsd3, nfsd3-ops,
        nfsd4-ops, nfsstat4, ntp, postfix, power, proc-count, qmail, redis, rpc, rpcd, sendmail, snmp-cpu, snmp-load, snmp-mem,
        snmp-net, snmp-net-err, snmp-sys, snooze, squid, test, thermal, top-bio, top-bio-adv, top-childwait, top-cpu, top-cpu-adv,
        top-cputime, top-cputime-avg, top-int, top-io, top-io-adv, top-latency, top-latency-avg, top-mem, top-oom, utmp, vm-cpu,
        vm-mem, vm-mem-adv, vmk-hba, vmk-int, vmk-nic, vz-cpu, vz-io, vz-ubc, wifi, zfs-arc, zfs-l2arc, zfs-zil

STEPS TO REPRODUCE

md0 is raid10 comprised of sda, sdb,sdc,sdd
Raid layout is far with 2 copies

numbers for total and all disks are correct.
md0 should be the same as total in this case

dstat -dD md0,sda,sdb,sdc,sdd,total 60

--dsk/md0-----dsk/sda-----dsk/sdb-----dsk/sdc-----dsk/sdd----dsk/total-
  31M   34M:  37M   24M:  37M   24M:  37M   24M:  37M   24M: 149M   97M
 238M  446k:  20M  121k:  20M  123k:  20M  128k:  20M  125k:  78M  498k
 280M  409k:  22M  104k:  22M  106k:  22M  107k:  22M  106k:  90M  423k
 281M  371k:  22M   94k:  22M   94k:  22M   95k:  22M   95k:  90M  379k
 280M  404k:  22M  103k:  22M  103k:  22M  104k:  22M  104k:  90M  413k
 
md0: 280M
sda+sdb+sdc+sdd: 88M
total: 90M (+-88M)

EXPECTED RESULTS

md0: 88-90M

ACTUAL RESULTS

combined result for raid disk way off