Mailing List Archive

cgroups blkio with tapdisk
Hi

I am facing anissue and I am not exactly sure what i am doing is the right
approch

my aim is to throttle IO on tapdisk disk (xenserver/xcp-ng , the disk is
nfs mounted VHD)

I tried to use cgroup blkio for that but it seems it is not working and I
am not sure if blkio support this scenario or not

the steps i did are the following
1- find the tabdisk that belong to the vm I want to throttle using tap-ctl
list
2- find major minor numbers using tap-ctl list and lsblk
3- doing this command
echo "254:161 1048576" >
/sys/fs/cgroup/blkio/vm.slice/blkio.throttle.write_bps_device

the tapdisk process id is already in vm.slice

doing dd with direct flag i still get full disk write speed

any thoughts ?

Thanks