[3/3] qemu-iotests: Test postcopy migration

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/181     | 117 +++++++++++++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/181.out |  38 +++++++++++++++
 tests/qemu-iotests/group   |   1 +
 3 files changed, 156 insertions(+)
 create mode 100755 tests/qemu-iotests/181
 create mode 100644 tests/qemu-iotests/181.out

On 04/13/2017 12:23 PM, Kevin Wolf wrote:
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  tests/qemu-iotests/181     | 117 +++++++++++++++++++++++++++++++++++++++++++++
>  tests/qemu-iotests/181.out |  38 +++++++++++++++
>  tests/qemu-iotests/group   |   1 +
>  3 files changed, 156 insertions(+)
>  create mode 100755 tests/qemu-iotests/181
>  create mode 100644 tests/qemu-iotests/181.out
> 

I don't see a 180.out mentioned on-list anywhere (but the choice of test
number is not too serious).

./check -raw 181

 === Write something on the source ===

+WARNING: Image format was not specified for 'TEST_DIR/t.raw' and
probing guessed raw.
+Automatically detecting the format is dangerous for raw images, write
operations on block 0 will be restricted.
+Specify the 'raw' format explicitly to remove the restrictions.


You'll want to fix that.


> +# Slow down migration so much that it definitely won't finish before we can
> +# switch to postcopy
> +silent=yes
> +_send_qemu_cmd $src 'migrate_set_speed 4k' "(qemu)"
> +_send_qemu_cmd $src 'migrate_set_capability postcopy-ram on' "(qemu)"
> +_send_qemu_cmd $src "migrate -d unix:${MIG_SOCKET}" "(qemu)"
> +_send_qemu_cmd $src 'migrate_start_postcopy' "(qemu)"
> +
> +QEMU_COMM_TIMEOUT=1 qemu_cmd_repeat=10 silent=yes \
> +    _send_qemu_cmd $src "info migrate" "completed\|failed"
> +silent=yes _send_qemu_cmd $src "" "(qemu)"

Do we want to tell the source to go back to a higher migrate_set_speed
once we know we are in postcopy mode?  But the test passed for me under
-qcow2 in less than 2 seconds, on an unloaded machine, so hopefully even
on a heavily loaded machine we aren't giving up due to timeouts.

* Kevin Wolf (kwolf@redhat.com) wrote:
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  tests/qemu-iotests/181     | 117 +++++++++++++++++++++++++++++++++++++++++++++
>  tests/qemu-iotests/181.out |  38 +++++++++++++++
>  tests/qemu-iotests/group   |   1 +
>  3 files changed, 156 insertions(+)
>  create mode 100755 tests/qemu-iotests/181
>  create mode 100644 tests/qemu-iotests/181.out
> 
> diff --git a/tests/qemu-iotests/181 b/tests/qemu-iotests/181
> new file mode 100755
> index 0000000..563aee7
> --- /dev/null
> +++ b/tests/qemu-iotests/181
> @@ -0,0 +1,117 @@
> +#!/bin/bash
> +#
> +# Test postcopy live migration with shared storage
> +#
> +# Copyright (C) 2017 Red Hat, Inc.
> +#
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 2 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> +#
> +
> +# creator
> +owner=kwolf@redhat.com
> +
> +seq=`basename $0`
> +echo "QA output created by $seq"
> +
> +here=`pwd`
> +status=1	# failure is the default!
> +
> +MIG_SOCKET="${TEST_DIR}/migrate"
> +
> +_cleanup()
> +{
> +    rm -f "${MIG_SOCKET}"
> +	_cleanup_test_img
> +    _cleanup_qemu
> +}
> +trap "_cleanup; exit \$status" 0 1 2 3 15
> +
> +# get standard environment, filters and checks
> +. ./common.rc
> +. ./common.filter
> +. ./common.qemu
> +
> +_supported_fmt generic
> +_supported_proto generic
> +_supported_os Linux
> +
> +size=64M
> +_make_test_img $size
> +
> +echo
> +echo === Starting VMs ===
> +echo
> +
> +qemu_comm_method="monitor"
> +
> +_launch_qemu -drive file="${TEST_IMG}",cache=${CACHEMODE},id=disk
> +src=$QEMU_HANDLE
> +
> +_launch_qemu -drive file="${TEST_IMG}",cache=${CACHEMODE},id=disk \
> +             -incoming "unix:${MIG_SOCKET}"
> +dest=$QEMU_HANDLE
> +
> +echo
> +echo === Write something on the source ===
> +echo
> +
> +silent=
> +_send_qemu_cmd $src 'qemu-io disk "write -P 0x55 0 64k"' "(qemu)"
> +_send_qemu_cmd $src "" "ops/sec"
> +_send_qemu_cmd $src 'qemu-io disk "read -P 0x55 0 64k"' "(qemu)"
> +_send_qemu_cmd $src "" "ops/sec"
> +
> +echo
> +echo === Do postcopy migration to destination ===
> +echo
> +
> +# Slow down migration so much that it definitely won't finish before we can
> +# switch to postcopy
> +silent=yes
> +_send_qemu_cmd $src 'migrate_set_speed 4k' "(qemu)"
> +_send_qemu_cmd $src 'migrate_set_capability postcopy-ram on' "(qemu)"

You should probably also set this on the destination as well;  we
do it in pretty much all the places where we use postcopy, but I think
it'll work without it.

However,

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> +_send_qemu_cmd $src "migrate -d unix:${MIG_SOCKET}" "(qemu)"
> +_send_qemu_cmd $src 'migrate_start_postcopy' "(qemu)"
> +
> +QEMU_COMM_TIMEOUT=1 qemu_cmd_repeat=10 silent=yes \
> +    _send_qemu_cmd $src "info migrate" "completed\|failed"
> +silent=yes _send_qemu_cmd $src "" "(qemu)"
> +
> +echo
> +echo === Do some I/O on the destination ===
> +echo
> +
> +# It is important that we use the BlockBackend of the guest device here instead
> +# of the node name, which would create a new BlockBackend and not test whether
> +# the guest has the necessary permissions to access the image now
> +silent=
> +_send_qemu_cmd $dest 'qemu-io disk "read -P 0x55 0 64k"' "(qemu)"
> +_send_qemu_cmd $dest "" "ops/sec"
> +_send_qemu_cmd $dest 'qemu-io disk "write -P 0x66 1M 64k"' "(qemu)"
> +_send_qemu_cmd $dest "" "ops/sec"
> +
> +echo
> +echo === Shut down and check image ===
> +echo
> +
> +_send_qemu_cmd $src 'quit' ""
> +_send_qemu_cmd $dest 'quit' ""
> +wait=1 _cleanup_qemu
> +
> +_check_test_img
> +
> +# success, all done
> +echo "*** done"
> +rm -f $seq.full
> +status=0
> diff --git a/tests/qemu-iotests/181.out b/tests/qemu-iotests/181.out
> new file mode 100644
> index 0000000..6534ba2
> --- /dev/null
> +++ b/tests/qemu-iotests/181.out
> @@ -0,0 +1,38 @@
> +QA output created by 181
> +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
> +
> +=== Starting VMs ===
> +
> +
> +=== Write something on the source ===
> +
> +QEMU X.Y.Z monitor - type 'help' for more information
> +(qemu) qemu-io disk "write -P 0x55 0 64k"
> +wrote 65536/65536 bytes at offset 0
> +64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> +(qemu) 
> +(qemu) qemu-io disk "read -P 0x55 0 64k"
> +read 65536/65536 bytes at offset 0
> +64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> +
> +=== Do postcopy migration to destination ===
> +
> +
> +=== Do some I/O on the destination ===
> +
> +QEMU X.Y.Z monitor - type 'help' for more information
> +(qemu) qemu-io disk "read -P 0x55 0 64k"
> +read 65536/65536 bytes at offset 0
> +64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> +(qemu) 
> +(qemu) qemu-io disk "write -P 0x66 1M 64k"
> +wrote 65536/65536 bytes at offset 1048576
> +64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> +
> +=== Shut down and check image ===
> +
> +(qemu) quit
> +(qemu) 
> +(qemu) quit
> +No errors were found on the image.
> +*** done
> diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
> index 43142dd..893962d 100644
> --- a/tests/qemu-iotests/group
> +++ b/tests/qemu-iotests/group
> @@ -169,3 +169,4 @@
>  174 auto
>  175 auto quick
>  176 rw auto backing
> +181 rw auto migration
> -- 
> 1.8.3.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Am 13.04.2017 um 20:44 hat Eric Blake geschrieben:
> On 04/13/2017 12:23 PM, Kevin Wolf wrote:
> > Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> > ---
> >  tests/qemu-iotests/181     | 117 +++++++++++++++++++++++++++++++++++++++++++++
> >  tests/qemu-iotests/181.out |  38 +++++++++++++++
> >  tests/qemu-iotests/group   |   1 +
> >  3 files changed, 156 insertions(+)
> >  create mode 100755 tests/qemu-iotests/181
> >  create mode 100644 tests/qemu-iotests/181.out
> > 
> 
> I don't see a 180.out mentioned on-list anywhere (but the choice of test
> number is not too serious).

It's used by this one: [PATCH 00/18] nbd: BLOCK_STATUS

> ./check -raw 181
> 
>  === Write something on the source ===
> 
> +WARNING: Image format was not specified for 'TEST_DIR/t.raw' and
> probing guessed raw.
> +Automatically detecting the format is dangerous for raw images, write
> operations on block 0 will be restricted.
> +Specify the 'raw' format explicitly to remove the restrictions.
> 
> 
> You'll want to fix that.

Thanks for catching this, will fix.

> > +# Slow down migration so much that it definitely won't finish before we can
> > +# switch to postcopy
> > +silent=yes
> > +_send_qemu_cmd $src 'migrate_set_speed 4k' "(qemu)"
> > +_send_qemu_cmd $src 'migrate_set_capability postcopy-ram on' "(qemu)"
> > +_send_qemu_cmd $src "migrate -d unix:${MIG_SOCKET}" "(qemu)"
> > +_send_qemu_cmd $src 'migrate_start_postcopy' "(qemu)"
> > +
> > +QEMU_COMM_TIMEOUT=1 qemu_cmd_repeat=10 silent=yes \
> > +    _send_qemu_cmd $src "info migrate" "completed\|failed"
> > +silent=yes _send_qemu_cmd $src "" "(qemu)"
> 
> Do we want to tell the source to go back to a higher migrate_set_speed
> once we know we are in postcopy mode?  But the test passed for me under
> -qcow2 in less than 2 seconds, on an unloaded machine, so hopefully even
> on a heavily loaded machine we aren't giving up due to timeouts.

After switching to postcopy mode, the limits aren't applied any more
anyway (because the running VM is actively waiting for the pages and we
don't want to stall it artificially).

Kevin