On 25.08.2015 18:54, Dmitry Guryanov wrote:
> On 08/25/2015 12:04 PM, nshirokovs...@virtuozzo.com wrote:
>> From: Nikolay Shirokovskiy <nshirokovs...@virtuozzo.com>
>>
>> Migration API has a lot of options. This patch intention is to provide
>> support for those options that can be trivially supported and give
>> estimation for other options support in this commit message.
>>
>> I. Supported.
>>
>> 1. VIR_MIGRATE_COMPRESSED. Means 'use compression when migration domain
>> memory'. It is supported but quite uncommon way: vz migration demands that
>> this
>> option should be set. This is due to vz is hardcoded to moving VMs memory
>> using
>> compression. So anyone who wants to migrate vz domain should set this option
>> thus declaring it knows it uses compression.
>>
>> Why bother? May be just support this option and ignore if it is not set or
>> don't support at all as we can't change behaviour in this aspect. Well I
>> believe that this option is, first, inherent to hypervisor implementation as
>> we have a task of moving domain memory to different place and, second, we
>> have
>> a tradeoff here between cpu and network resources and some managment should
>> choose the stratery via this option. If we choose ignoring or unsupporting
>> implementation than this option has a too vague meaning. Let's go into more
>> detail.
>>
>> First if we ignore situation where option is not set than we put user into
>> fallacy that vz hypervisor don't use compression and thus have lower cpu
>> usage. Second approach is to not support the option. The main reason not to
>> follow this way is that 'not supported and not set' is indistinguishable from
>> 'supported and not set' and thus again fool the user.
>>
>> 2. VIR_MIGRATE_LIVE. Means 'reduce domain downtime by suspending it as lately
>> as possible' which technically means 'migrate as much domain memory as
>> possible
>> before suspending'. Supported in same manner as VIR_MIGRATE_COMPRESSED as
>> both
>> vz VMs and CTs are always migrated via live scheme.
>>
>> One may be fooled by vz sdk flags of migration api: PVMT_HOT_MIGRATION(aka
>> live) and PVMT_WARM_MIGRATION(aka normal). Current implementation ignore
>> these
>> flags and always use live migration.
>>
>> 3. VIR_MIGRATE_PERSIST_DEST, VIR_MIGRATE_UNDEFINE_SOURCE. This two comes
>> together. Vz domain are alwasy persistent so we have to support demand option
>> VIR_MIGRATE_PERSIST_DEST is set and VIR_MIGRATE_UNDEFINE_SOURCE is not (and
>> this is done just by unsupporting it).
>>
>> 4. VIR_MIGRATE_PAUSED. Means 'don't resume domain on destination'. This is
>> trivially supported as we have a corresponding option in vz migration.
>>
>> 5. VIR_MIGRATE_OFFLINE. Means 'migrate only XML definition of a domain'. It
>> is
>> a forcing option that is it is ignored if domain is running and must be set
>> to migrate stopped domain. Vz implemenation follows this unformal definition
>> with one exception: non-shared disks will be migrated too. This desicion is
>> on
>> par with VIR_MIGRATE_NON_SHARED_DISK condideration(see last part of this
>> notes).
>>
>> All that said the minimal command to migrate vz domain looks next:
>>
>> migrate --direct $DOMAIN $STUB --migrateuri $DESTINATION --live --persistent
>> --compressed.
>>
>> Not good. Say if you want to just migrate a domain without further
>> details you will get error messages until you add these options to
>> command line. I think there is a lack of notion 'default' behaviour
>> in all these aspects. If we have it we could just issue:
>>
>> migrate $DOMAIN $DESTINATION
>>
>> For vz this would give default compression for example, for qemu - default
>> no-compression. Then we could have flags --compressed and -no-compressed
>> and for vz the latter would give unsupported error.
>>
>> II. Unsupported.
>>
>> 1. VIR_MIGRATE_UNSAFE. Vz disks are always have 'cache=none' set (this
>> is not reflected in current version of vz driver and will be fixed
>> soon). So we need not to support this option.
>>
>> 2. VIR_MIGRATE_CHANGE_PROTECTION. Unsupported as we have no appopriate
>> support from vz sdk. Although we have locks they are advisory and
>> cant help us.
>>
>> 3. VIR_MIGRATE_TUNNELLED. Means 'use libvirtd to libvirtd connection
>> to pass hypervisor migration traffic'. Unsupported as not among
>> vz hypervisor usecases.
>>
>> 4. p2p migration which is exposed via *toURI* interface with
>> VIR_MIGRATE_PEER2PEER flag set. It doesn't make sense
>> for vz migration as it is a variant of managed migration which
>> is qemu specific.
>>
>> 5. VIR_MIGRATE_ABORT_ON_ERROR, VIR_MIGRATE_AUTO_CONVERGE,
>> VIR_MIGRATE_RDMA_PIN_ALL, VIR_MIGRATE_NON_SHARED_INC,
>> VIR_MIGRATE_PARAM_DEST_XML, VIR_MIGRATE_PARAM_BANDWIDTH,
>> VIR_MIGRATE_PARAM_GRAPHICS_URI, VIR_MIGRATE_PARAM_LISTEN_ADDRESS,
>> VIR_MIGRATE_PARAM_MIGRATE_DISKS.
>> Without further discussion. They are just not usecases of vz hypevisor.
>>
>> III. Undecided and thus unsupported.
>>
>> 6. VIR_MIGRATE_NON_SHARED_DISK. The meaning of this option is not clear to
>> me.
>> Look, if qemu domain has a non-shared disk than it will refuse to migrate.
>> But
>> after you specify this option it will refuse too. You need to create image
>> file
>> for the disk on the destination side. Only after that you can migrate.
>> Unexpectedly existence of this file is enough to migrate without option too.
>> In
>> this case you will get a domain on the destination with disk image unrelated
>> to
>> source one and this is in case of live migration! Looks like a bug. Ok,
>> imagine
>> this is fixed so that migration of non-shared disk is only possible with
>> actual coping disk to destination. What we get from this option? We get
>> that you have to specify this option if you want to migrate a domain with
>> non-shared disk like some forcing option. May be it is a good approach
>> but it is incompatible with vz. Vz don't demand any user awareness of
>> migration of non-shared disks. And this case incompatibility can not
>> be easily resolved as for 'compressed' option as this option depends on
>> classifying of shared/non-shared for disks which is done inside vz.
>> vz: implement misc migration options
>>
>> Signed-off-by: Nikolay Shirokovskiy <nshirokovs...@virtuozzo.com>
>> ---
>> src/vz/vz_driver.c | 128
>> +++++++++++++++++++++++++++++++++++++++++++++++++++-
>> src/vz/vz_sdk.c | 8 +++-
>> src/vz/vz_sdk.h | 3 +-
>> 3 files changed, 134 insertions(+), 5 deletions(-)
>>
>> diff --git a/src/vz/vz_driver.c b/src/vz/vz_driver.c
>> index dc26b09..b12592b 100644
>> --- a/src/vz/vz_driver.c
>> +++ b/src/vz/vz_driver.c
>> @@ -1465,7 +1465,120 @@ vzMakeVzUri(const char *connuri_str)
>> return vzuri;
>> }
>> -#define VZ_MIGRATION_FLAGS (0)
>> +virURIPtr
>> +vzParseVzURI(const char *uri_str)
>> +{
>> + virURIPtr uri = NULL;
>> + int ret = -1;
>> +
>> + if (!(uri = virURIParse(uri_str)))
>> + goto cleanup;
>> +
>> + if (uri->scheme == NULL || uri->server == NULL) {
>> + virReportError(VIR_ERR_INVALID_ARG,
>> + _("scheme and host are mandatory vz migration URI:
>> %s"),
>> + uri_str);
>> + goto cleanup;
>> + }
>> +
>> + if (uri->user != NULL || uri->path != NULL ||
>> + uri->query != NULL || uri->fragment != NULL) {
>> + virReportError(VIR_ERR_INVALID_ARG,
>> + _("only scheme, host and port are supported in "
>> + "vz migration URI: %s"), uri_str);
>> + goto cleanup;
>> + }
>> +
>> + if (STRNEQ(uri->scheme, "tcp")) {
>> + virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED,
>> + _("unsupported scheme %s in migration URI %s"),
>> + uri->scheme, uri_str);
>> + goto cleanup;
>> + }
>> +
>
> Try URI vz+ssh://hotname:22/system, there is some bug, prlsdk returns error
> after migration:
It is ok. Uri you pass with --migrateuri is hypervisor connection uri and port
should be appropriate, not ssh one.
>
> 2015-08-25 15:36:18.923+0000: 92650: error : virDomainGetJobInfo:8889 : this
> function is not supported by the connection driver: virDomainGetJobInfo
> 2015-08-25 15:36:19.169+0000: 92649: error : prlsdkMigrate:4089 : internal
> error: Unable to connect to the server "10.27.255.18". An invalid response
> has been received from the server. Make sure that Parallels Server is running
> on the server "10.27.255.18" and is up to date and try again.
>
>> + ret = 0;
>> +
>> + cleanup:
>> + if (ret < 0) {
>> + virURIFree(uri);
>> + uri = NULL;
>> + }
>> +
>> + return uri;
>> +}
>> +
>> +#define VZ_MIGRATION_FLAGS \
>> + (VIR_MIGRATE_OFFLINE | \
>> + VIR_MIGRATE_LIVE | \
>> + VIR_MIGRATE_COMPRESSED | \
>> + VIR_MIGRATE_PERSIST_DEST | \
>> + VIR_MIGRATE_PAUSED)
>> +
>> +/* TODO this code should be in common place as these
>> + rules follows from options (informal) definitions.
>> + Qemu makes some of these checks on begin phase but not all. */
>> +int vzCheckOfflineFlags(int flags)
>> +{
>> + if (!(flags & VIR_MIGRATE_OFFLINE)) {
>> + virReportError(VIR_ERR_OPERATION_INVALID,
>> + "%s", _("domain is not running"));
>> + return -1;
>> + }
>> +
>> + if (flags & VIR_MIGRATE_LIVE) {
>> + virReportError(VIR_ERR_OPERATION_INVALID, "%s",
>> + _("live offline migration does not "
>> + "make sense"));
>> + return -1;
>> + }
>> +
>> + if (flags & VIR_MIGRATE_COMPRESSED) {
>> + virReportError(VIR_ERR_OPERATION_INVALID, "%s",
>> + _("compressed offline migration does not "
>> + "make sense"));
>> + return -1;
>> + }
>> +
>> + if (flags & VIR_MIGRATE_PAUSED) {
>> + virReportError(VIR_ERR_OPERATION_INVALID, "%s",
>> + _("paused offline migration does not "
>> + "make sense"));
>> + return -1;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +int vzCheckCommonFlags(int flags)
>> +{
>> + if (!(flags & VIR_MIGRATE_PERSIST_DEST)) {
>> + virReportError(VIR_ERR_INVALID_ARG, "%s",
>> + _("flags VIR_MIGRATE_PERSIST_DEST must be set"
>> + " for vz migration"));
>> + return -1;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +int vzCheckOnlineFlags(int flags)
>> +{
>> + if (!(flags & VIR_MIGRATE_LIVE)) {
>> + virReportError(VIR_ERR_INVALID_ARG, "%s",
>> + _("flags VIR_MIGRATE_LIVE must be set"
>> + " for online vz migration"));
>> + return -1;
>> + }
>> +
>> + if (!(flags & VIR_MIGRATE_COMPRESSED)) {
>> + virReportError(VIR_ERR_INVALID_ARG, "%s",
>> + _("flags VIR_MIGRATE_COMPRESSED must be set"
>> + " for online vz migration"));
>> + return -1;
>> + }
>> +
>> + return 0;
>> +}
>> static int
>> vzDomainMigratePerform3(virDomainPtr domain,
>> @@ -1491,12 +1604,23 @@ vzDomainMigratePerform3(virDomainPtr domain,
>> virCheckFlags(VZ_MIGRATION_FLAGS, -1);
>> + if (vzCheckCommonFlags(flags))
>> + goto cleanup;
>> +
>> if (!(vzuri = vzMakeVzUri(uri)))
>> goto cleanup;
>> if (!(dom = vzDomObjFromDomain(domain)))
>> goto cleanup;
>> + if (virDomainObjIsActive(dom))
>> + ret = vzCheckOnlineFlags(flags);
>> + else
>> + ret = vzCheckOfflineFlags(flags);
>> +
>> + if (ret < 0)
>> + goto cleanup;
>> +
>> dconn = virConnectOpen(uri);
>> if (dconn == NULL) {
>> virReportError(VIR_ERR_OPERATION_FAILED,
>> @@ -1513,7 +1637,7 @@ vzDomainMigratePerform3(virDomainPtr domain,
>> if (vzParseCookie(cookie, session_uuid) < 0)
>> goto cleanup;
>> - if (prlsdkMigrate(dom, vzuri, session_uuid, dname) < 0)
>> + if (prlsdkMigrate(dom, vzuri, session_uuid, dname, flags) < 0)
>> goto cleanup;
>> virDomainObjListRemove(privconn->domains, dom);
>> diff --git a/src/vz/vz_sdk.c b/src/vz/vz_sdk.c
>> index 89a2429..9a2b5df 100644
>> --- a/src/vz/vz_sdk.c
>> +++ b/src/vz/vz_sdk.c
>> @@ -4065,18 +4065,22 @@ prlsdkGetMemoryStats(virDomainObjPtr dom,
>> int prlsdkMigrate(virDomainObjPtr dom, virURIPtr uri,
>> const unsigned char *session_uuid,
>> - const char *dname)
>> + const char *dname, unsigned int flags)
>> {
>> int ret = -1;
>> vzDomObjPtr privdom = dom->privateData;
>> PRL_HANDLE job = PRL_INVALID_HANDLE;
>> char uuidstr[VIR_UUID_STRING_BUFLEN + 2];
>> + PRL_UINT32 vzflags = PRLSDK_MIGRATION_FLAGS;
>> +
>> + if (flags & VIR_MIGRATE_PAUSED)
>> + vzflags |= PVMT_DONT_RESUME_VM;
>> prlsdkUUIDFormat(session_uuid, uuidstr);
>> job = PrlVm_MigrateWithRenameEx(privdom->sdkdom, uri->server,
>> uri->port, uuidstr,
>> dname == NULL ? "" : dname,
>> "", /* use default dir for migrated
>> instance bundle */
>> - PRLSDK_MIGRATION_FLAGS,
>> + vzflags,
>> 0, /* reserved flags */
>> PRL_TRUE /* don't ask for
>> confirmations */
>> );
>> diff --git a/src/vz/vz_sdk.h b/src/vz/vz_sdk.h
>> index 0aa70b3..5b26b70 100644
>> --- a/src/vz/vz_sdk.h
>> +++ b/src/vz/vz_sdk.h
>> @@ -80,4 +80,5 @@ int
>> prlsdkMigrate(virDomainObjPtr dom,
>> virURIPtr uri,
>> const char unsigned *session_uuid,
>> - const char *dname);
>> + const char *dname,
>> + unsigned int flags);
>
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