Storage testing

Posted May 28, 2019 21:08 UTC (Tue) by jhoblitt (subscriber, #77733)
Parent article: Storage testing

I would think that a runc/docker image would solve all of the environmental issues except for which kernel modules need to be available. Docker in a qemu vagrant box should be a complete solution. That makes it easy to change kernel versions.

Storage testing

Posted May 28, 2019 21:37 UTC (Tue) by tytso (subscriber, #9993) [Link] (1 responses)

Docker adds no real value, and in fact, to the extent that tries to insulate the container from the real hardware, it gets in the way. Yes, you can run in privleged mode, but at that point, docker is no more than a fancy tar.gz plus a chroot.

It's setting up all of the qemu configuration to run the storage testing which is where the real value lies. For example, this is what "kvm-xfstests smoke" runs:

ionice -n 5 /usr/bin/kvm -boot order=c -net none -machine type=pc,accel=kvm:tcg -cpu host -drive file=/usr/projects/xfstests-bld/build-64/kvm-xfstests/test-appliance/root_fs.img,if=virtio,snapshot=on -drive file=/dev/lambda/test-4k,cache=none,if=virtio,format=raw,aio=native -drive file=/dev/lambda/scratch,cache=none,if=virtio,format=raw,aio=native -drive file=/dev/lambda/test-1k,cache=none,if=virtio,format=raw,aio=native -drive file=/dev/lambda/scratch2,cache=none,if=virtio,format=raw,aio=native -drive file=/dev/lambda/scratch3,cache=none,if=virtio,format=raw,aio=native -drive file=/dev/lambda/results,cache=none,if=virtio,format=raw,aio=native -drive file=/tmp/xfstests-cli.VpexZxAo/kvm-vdh,if=virtio,format=raw -vga none -nographic -smp 2 -m 2048 -fsdev local,id=v_tmp,path=/tmp/kvm-xfstests-tytso,security_model=none -device virtio-9p-pci,fsdev=v_tmp,mount_tag=v_tmp -object rng-random,filename=/dev/urandom,id=rng0 -device virtio-rng-pci,rng=rng0 -serial mon:stdio -monitor telnet:localhost:7498,server,nowait -serial telnet:localhost:7500,server,nowait -serial telnet:localhost:7501,server,nowait -serial telnet:localhost:7502,server,nowait -gdb tcp:localhost:7499 --kernel /build/ext4-64/arch/x86/boot/bzImage --append quiet loglevel=0 root=/dev/vda console=ttyS0,115200 fstestcfg=4k fstestset=-g,quick fstestopt=aex fstesttz=America/New_York fstesttyp=ext4 fstestapi=1.5

... and where the root_fs.img can be downloaded here[1], and built from scratch using directions here[2].

[1] https://www.kernel.org/pub/linux/kernel/people/tytso/kvm-...
[2] https://github.com/tytso/xfstests-bld/blob/master/Documen...

Changing kernel versions is just a matter of pointing qemu at the kernel in the build tree: --kernel /build/ext4-64/arch/x86/boot/bzImage

And why bother with a docker image when you can just use a qemu image file: -drive file=/usr/projects/xfstests-bld/build-64/kvm-xfstests/test-appliance/root_fs.img,if=virtio,snapshot=on

Docker doesn't help you with any of the rest, which includes setting up storage devices that should be used for testing. So why use Docker?

Storage testing

Posted May 29, 2019 10:37 UTC (Wed) by unixbhaskar (guest, #44758) [Link]

Right, Ted. I was wondering how come that Docker fellow come into the picture of this kind "low level" stuff, which needs lots low-level access and tweaking.

Any container mechanism is certainly not built for this kind stuff in mind nor help greatly in the purpose.