[PATCH v8 0/5] Migration deprecated parts

[PATCH v8 0/5] Migration deprecated parts

[Juan Quintela]

Based on: Message-ID: <20231018100651.32674-1-quintela@redhat.com>
          [PULL 00/11] Migration 20231018 patches

v8 now:
- drop changes to 183.out
- create _filter_migration_block_deprecated

And now it passes the iotests.

Please review patch 1.
Rest are unchanged from v6.

Later, Juan.

And here we are, at v7:
- drop black line at the end of deprecated.rst
- change qemu-iotest output due to warnings for deprecation.

The only real change is the output of the qemu-iotest.  That is the
reason why I maintained the reviewed-by.  But will be happy if anyone
of the block people ack the changes.

Thanks, Juan.

On this v6:
- Fixed Markus comments
- 1st patch is reviewed
- dropped the RFC ones.

Later, Juan.

On this v5:
- Rebased on top of last migration pull requesnt:

- address markus comments.  Basically we recommend always
  blockdev-mirror + NBD.  In deprecated.rst we also put the posiblity
  of using block-incremental and block, but we state that they are
  also deprecated.
  I know, I know, I deprecated them in the following patch.

- Dropped the removal of block-migration and block-incremental I am
  only interested in showing why I want to remove the -b/-i options.

Please review.

Later, Juan.

On this v4:
- addressed all markus comments.
- rebased on latest.
- improve formatting of migration.json
- print block migration status when needed.
- patches 7-10 are not mean to merge, they just show why we want to
  deprecate block migration and remove its support.
- Patch 7 just drop support for -i/-b and qmp equivalents.
- Patch 8 shows all the helpers and convolutions we need to have to
  support that -i and -d.
- patch 9 drops block-incremental migration support.
- patch 9 drops block migration support.

Please review.

Thanks, Juan.

On this v3:

- Rebase on top of upstream.
- Changed v8.1 to 8.2 (I left the reviewed by anyways)
- missing the block deprecation code, please.

Please, review.

Later, Juan.

On this v2:

- dropped -incoming <uri> deprecation
  Paolo came with a better solution using keyvalues.

- skipped field is already ready for next pull request, so dropped.

- dropped the RFC bits, nermal PATCH.

- Assessed all the review comments.

- Added indentation of migration.json.

- Used the documentation pointer to substitute block migration.

Please review.

[v1]
Hi this series describe the migration parts that have to be deprecated.

- It is an rfc because I doubt that I did the deprecation process right. Hello Markus O:-)

- skipped field: It is older than me, I have never know what it stands
  for.  As far as I know it has always been zero.

- inc/blk migrate command options.  They are only used by block
  migration (that I deprecate on the following patch).  And they are really bad.
  grep must_remove_block_options.

- block migration.  block jobs, whatever they are called this week are
  way more flexible.  Current code works, but we broke it here and
  there, and really nobody has stand up to maintain it.  It is quite
  contained and can be left there.  Is anyone really using it?

- old compression method.  It don't work.  See last try from Lukas to
  make a test that works reliabely.  I failed with the same task years
  ago.  It is really slow, and if compression is good for you, multifd
  + zlib is going to perform/compress way more.

  I don't know what to do with this code, really.

  * Remove it for this release?  It don't work, and haven't work
    reliabely in quite a few time.

  * Deprecate it and remove in another couple of releases, i.e. normal
    deprecation.

  * Ideas?

- -incoming <uri>

  if you need to set parameters (multifd cames to mind, and preempt has
  the same problem), you really needs to use defer.  So what should we do here?

  This part is not urget, because management apps have a working
  option that are already using "defer", and the code simplifacation
  if we remove it is not so big.  So we can leave it until 9.0 or
  whatever we think fit.

What do you think?

Later, Juan.

Juan Quintela (5):
  qemu-iotests: Filter warnings about block migration being deprecated
  migration: migrate 'inc' command option is deprecated.
  migration: migrate 'blk' command option is deprecated.
  migration: Deprecate block migration
  migration: Deprecate old compression method

 docs/about/deprecated.rst        | 35 ++++++++++++
 qapi/migration.json              | 93 ++++++++++++++++++++++++--------
 migration/block.c                |  3 ++
 migration/migration-hmp-cmds.c   | 10 ++++
 migration/migration.c            | 10 ++++
 migration/options.c              | 22 +++++++-
 tests/qemu-iotests/183           |  2 +-
 tests/qemu-iotests/common.filter |  7 +++
 8 files changed, 158 insertions(+), 24 deletions(-)

-- 
2.41.0

[PATCH v8 1/5] qemu-iotests: Filter warnings about block migration being deprecated

[Juan Quintela]

Create a new filter that removes the two warnings for test 183.

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 tests/qemu-iotests/183           | 2 +-
 tests/qemu-iotests/common.filter | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/183 b/tests/qemu-iotests/183
index ee62939e72..b85770458e 100755
--- a/tests/qemu-iotests/183
+++ b/tests/qemu-iotests/183
@@ -90,7 +90,7 @@ echo
 reply="$(_send_qemu_cmd $src \
     "{ 'execute': 'migrate',
        'arguments': { 'uri': 'unix:${MIG_SOCKET}', 'blk': true } }" \
-    'return\|error')"
+    'return\|error' | _filter_migration_block_deprecated)"
 echo "$reply"
 if echo "$reply" | grep "compiled without old-style" > /dev/null; then
     _notrun "migrate -b support not compiled in"
diff --git a/tests/qemu-iotests/common.filter b/tests/qemu-iotests/common.filter
index fc3c64bcb8..2846c83808 100644
--- a/tests/qemu-iotests/common.filter
+++ b/tests/qemu-iotests/common.filter
@@ -359,5 +359,12 @@ _filter_qcow2_compression_type_bit()
         -e 's/\(incompatible_features.*\), 3\(,.*\)/\1\2/'
 }
 
+# filter warnings caused for block migration deprecation
+_filter_migration_block_deprecated()
+{
+    gsed -e '/warning: parameter .blk. is deprecated; use blockdev-mirror with NBD instead/d' \
+         -e '/warning: block migration is deprecated; use blockdev-mirror with NBD instead/d'
+}
+
 # make sure this script returns success
 true
-- 
2.41.0

Re: [PATCH v8 1/5] qemu-iotests: Filter warnings about block migration being deprecated

[Hanna Czenczek]

On 18.10.23 13:55, Juan Quintela wrote:
> Create a new filter that removes the two warnings for test 183.
>
> Signed-off-by: Juan Quintela <quintela@redhat.com>
> ---
>   tests/qemu-iotests/183           | 2 +-
>   tests/qemu-iotests/common.filter | 7 +++++++
>   2 files changed, 8 insertions(+), 1 deletion(-)

Reviewed-by: Hanna Czenczek <hreitz@redhat.com>

Re: [PATCH v8 1/5] qemu-iotests: Filter warnings about block migration being deprecated

[Juan Quintela]

Hanna Czenczek <hreitz@redhat.com> wrote:
> On 18.10.23 13:55, Juan Quintela wrote:
>> Create a new filter that removes the two warnings for test 183.
>>
>> Signed-off-by: Juan Quintela <quintela@redhat.com>
>> ---
>>   tests/qemu-iotests/183           | 2 +-
>>   tests/qemu-iotests/common.filter | 7 +++++++
>>   2 files changed, 8 insertions(+), 1 deletion(-)
>
> Reviewed-by: Hanna Czenczek <hreitz@redhat.com>

Thanks.

[PATCH v8 2/5] migration: migrate 'inc' command option is deprecated.

[Juan Quintela]

Use blockdev-mirror with NBD instead.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 docs/about/deprecated.rst      | 8 ++++++++
 qapi/migration.json            | 8 +++++++-
 migration/migration-hmp-cmds.c | 5 +++++
 migration/migration.c          | 5 +++++
 4 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 2febd2d12f..fc6adf1dea 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -461,3 +461,11 @@ Migration
 ``skipped`` field in Migration stats has been deprecated.  It hasn't
 been used for more than 10 years.
 
+``inc`` migrate command option (since 8.2)
+''''''''''''''''''''''''''''''''''''''''''
+
+Use blockdev-mirror with NBD instead.
+
+As an intermediate step the ``inc`` functionality can be achieved by
+setting the ``block-incremental`` migration parameter to ``true``.
+But this parameter is also deprecated.
diff --git a/qapi/migration.json b/qapi/migration.json
index db3df12d6c..fa7f4f2575 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1524,6 +1524,11 @@
 #
 # @resume: resume one paused migration, default "off". (since 3.0)
 #
+# Features:
+#
+# @deprecated: Member @inc is deprecated.  Use blockdev-mirror with
+#     NBD instead.
+#
 # Returns: nothing on success
 #
 # Since: 0.14
@@ -1545,7 +1550,8 @@
 # <- { "return": {} }
 ##
 { 'command': 'migrate',
-  'data': {'uri': 'str', '*blk': 'bool', '*inc': 'bool',
+  'data': {'uri': 'str', '*blk': 'bool',
+           '*inc': { 'type': 'bool', 'features': [ 'deprecated' ] },
            '*detach': 'bool', '*resume': 'bool' } }
 
 ##
diff --git a/migration/migration-hmp-cmds.c b/migration/migration-hmp-cmds.c
index a82597f18e..83176f5bae 100644
--- a/migration/migration-hmp-cmds.c
+++ b/migration/migration-hmp-cmds.c
@@ -745,6 +745,11 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
     const char *uri = qdict_get_str(qdict, "uri");
     Error *err = NULL;
 
+    if (inc) {
+        warn_report("option '-i' is deprecated;"
+                    " use blockdev-mirror with NBD instead");
+    }
+
     qmp_migrate(uri, !!blk, blk, !!inc, inc,
                 false, false, true, resume, &err);
     if (hmp_handle_error(mon, err)) {
diff --git a/migration/migration.c b/migration/migration.c
index 05c0b801ba..27145cd99e 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1604,6 +1604,11 @@ static bool migrate_prepare(MigrationState *s, bool blk, bool blk_inc,
 {
     Error *local_err = NULL;
 
+    if (blk_inc) {
+        warn_report("parameter 'inc' is deprecated;"
+                    " use blockdev-mirror with NBD instead");
+    }
+
     if (resume) {
         if (s->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
             error_setg(errp, "Cannot resume if there is no "
-- 
2.41.0

[PATCH v8 3/5] migration: migrate 'blk' command option is deprecated.

[Juan Quintela]

Use blocked-mirror with NBD instead.

Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 docs/about/deprecated.rst      | 9 +++++++++
 qapi/migration.json            | 7 ++++---
 migration/migration-hmp-cmds.c | 5 +++++
 migration/migration.c          | 5 +++++
 4 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index fc6adf1dea..98b0f14e69 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -469,3 +469,12 @@ Use blockdev-mirror with NBD instead.
 As an intermediate step the ``inc`` functionality can be achieved by
 setting the ``block-incremental`` migration parameter to ``true``.
 But this parameter is also deprecated.
+
+``blk`` migrate command option (since 8.2)
+''''''''''''''''''''''''''''''''''''''''''
+
+Use blockdev-mirror with NBD instead.
+
+As an intermediate step the ``blk`` functionality can be achieved by
+setting the ``block`` migration capability to ``true``.  But this
+capability is also deprecated.
diff --git a/qapi/migration.json b/qapi/migration.json
index fa7f4f2575..3765c2b662 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1526,8 +1526,8 @@
 #
 # Features:
 #
-# @deprecated: Member @inc is deprecated.  Use blockdev-mirror with
-#     NBD instead.
+# @deprecated: Members @inc and @blk are deprecated.  Use
+#     blockdev-mirror with NBD instead.
 #
 # Returns: nothing on success
 #
@@ -1550,7 +1550,8 @@
 # <- { "return": {} }
 ##
 { 'command': 'migrate',
-  'data': {'uri': 'str', '*blk': 'bool',
+  'data': {'uri': 'str',
+           '*blk': { 'type': 'bool', 'features': [ 'deprecated' ] },
            '*inc': { 'type': 'bool', 'features': [ 'deprecated' ] },
            '*detach': 'bool', '*resume': 'bool' } }
 
diff --git a/migration/migration-hmp-cmds.c b/migration/migration-hmp-cmds.c
index 83176f5bae..dfe98da355 100644
--- a/migration/migration-hmp-cmds.c
+++ b/migration/migration-hmp-cmds.c
@@ -750,6 +750,11 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
                     " use blockdev-mirror with NBD instead");
     }
 
+    if (blk) {
+        warn_report("option '-b' is deprecated;"
+                    " use blockdev-mirror with NBD instead");
+    }
+
     qmp_migrate(uri, !!blk, blk, !!inc, inc,
                 false, false, true, resume, &err);
     if (hmp_handle_error(mon, err)) {
diff --git a/migration/migration.c b/migration/migration.c
index 27145cd99e..79b742b98b 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1609,6 +1609,11 @@ static bool migrate_prepare(MigrationState *s, bool blk, bool blk_inc,
                     " use blockdev-mirror with NBD instead");
     }
 
+    if (blk) {
+        warn_report("parameter 'blk' is deprecated;"
+                    " use blockdev-mirror with NBD instead");
+    }
+
     if (resume) {
         if (s->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
             error_setg(errp, "Cannot resume if there is no "
-- 
2.41.0

[PATCH v8 4/5] migration: Deprecate block migration

[Juan Quintela]

It is obsolete.  It is better to use driver-mirror with NBD instead.

CC: Kevin Wolf <kwolf@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Hanna Czenczek <hreitz@redhat.com>

Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 docs/about/deprecated.rst | 10 ++++++++++
 qapi/migration.json       | 29 ++++++++++++++++++++++++-----
 migration/block.c         |  3 +++
 migration/options.c       |  9 ++++++++-
 4 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 98b0f14e69..7ae872162d 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -478,3 +478,13 @@ Use blockdev-mirror with NBD instead.
 As an intermediate step the ``blk`` functionality can be achieved by
 setting the ``block`` migration capability to ``true``.  But this
 capability is also deprecated.
+
+block migration (since 8.2)
+'''''''''''''''''''''''''''
+
+Block migration is too inflexible.  It needs to migrate all block
+devices or none.
+
+Please see "QMP invocation for live storage migration with
+``blockdev-mirror`` + NBD" in docs/interop/live-block-operations.rst
+for a detailed explanation.
diff --git a/qapi/migration.json b/qapi/migration.json
index 3765c2b662..e3b00a215b 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -269,11 +269,15 @@
 #     average memory load of the virtual CPU indirectly.  Note that
 #     zero means guest doesn't dirty memory.  (Since 8.1)
 #
+# Features:
+#
+# @deprecated: Member @disk is deprecated because block migration is.
+#
 # Since: 0.14
 ##
 { 'struct': 'MigrationInfo',
   'data': {'*status': 'MigrationStatus', '*ram': 'MigrationStats',
-           '*disk': 'MigrationStats',
+           '*disk': { 'type': 'MigrationStats', 'features': [ 'deprecated' ] },
            '*vfio': 'VfioStats',
            '*xbzrle-cache': 'XBZRLECacheStats',
            '*total-time': 'int',
@@ -525,6 +529,9 @@
 #
 # Features:
 #
+# @deprecated: Member @block is deprecated.  Use blockdev-mirror with
+#     NBD instead.
+#
 # @unstable: Members @x-colo and @x-ignore-shared are experimental.
 #
 # Since: 1.2
@@ -534,7 +541,8 @@
            'compress', 'events', 'postcopy-ram',
            { 'name': 'x-colo', 'features': [ 'unstable' ] },
            'release-ram',
-           'block', 'return-path', 'pause-before-switchover', 'multifd',
+           { 'name': 'block', 'features': [ 'deprecated' ] },
+           'return-path', 'pause-before-switchover', 'multifd',
            'dirty-bitmaps', 'postcopy-blocktime', 'late-block-activate',
            { 'name': 'x-ignore-shared', 'features': [ 'unstable' ] },
            'validate-uuid', 'background-snapshot',
@@ -835,6 +843,9 @@
 #
 # Features:
 #
+# @deprecated: Member @block-incremental is deprecated.  Use
+#     blockdev-mirror with NBD instead.
+#
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
 #     are experimental.
 #
@@ -850,7 +861,7 @@
            'tls-creds', 'tls-hostname', 'tls-authz', 'max-bandwidth',
            'avail-switchover-bandwidth', 'downtime-limit',
            { 'name': 'x-checkpoint-delay', 'features': [ 'unstable' ] },
-           'block-incremental',
+           { 'name': 'block-incremental', 'features': [ 'deprecated' ] },
            'multifd-channels',
            'xbzrle-cache-size', 'max-postcopy-bandwidth',
            'max-cpu-throttle', 'multifd-compression',
@@ -1011,6 +1022,9 @@
 #
 # Features:
 #
+# @deprecated: Member @block-incremental is deprecated.  Use
+#     blockdev-mirror with NBD instead.
+#
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
 #     are experimental.
 #
@@ -1040,7 +1054,8 @@
             '*downtime-limit': 'uint64',
             '*x-checkpoint-delay': { 'type': 'uint32',
                                      'features': [ 'unstable' ] },
-            '*block-incremental': 'bool',
+            '*block-incremental': { 'type': 'bool',
+                                    'features': [ 'deprecated' ] },
             '*multifd-channels': 'uint8',
             '*xbzrle-cache-size': 'size',
             '*max-postcopy-bandwidth': 'size',
@@ -1225,6 +1240,9 @@
 #
 # Features:
 #
+# @deprecated: Member @block-incremental is deprecated.  Use
+#     blockdev-mirror with NBD instead.
+#
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
 #     are experimental.
 #
@@ -1251,7 +1269,8 @@
             '*downtime-limit': 'uint64',
             '*x-checkpoint-delay': { 'type': 'uint32',
                                      'features': [ 'unstable' ] },
-            '*block-incremental': 'bool',
+            '*block-incremental': { 'type': 'bool',
+                                    'features': [ 'deprecated' ] },
             '*multifd-channels': 'uint8',
             '*xbzrle-cache-size': 'size',
             '*max-postcopy-bandwidth': 'size',
diff --git a/migration/block.c b/migration/block.c
index b60698d6e2..acffe88f84 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -731,6 +731,9 @@ static int block_save_setup(QEMUFile *f, void *opaque)
     trace_migration_block_save("setup", block_mig_state.submitted,
                                block_mig_state.transferred);
 
+    warn_report("block migration is deprecated;"
+                " use blockdev-mirror with NBD instead");
+
     ret = init_blk_migration(f);
     if (ret < 0) {
         return ret;
diff --git a/migration/options.c b/migration/options.c
index 42fb818956..a753eae438 100644
--- a/migration/options.c
+++ b/migration/options.c
@@ -12,6 +12,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/error-report.h"
 #include "exec/target_page.h"
 #include "qapi/clone-visitor.h"
 #include "qapi/error.h"
@@ -473,10 +474,14 @@ bool migrate_caps_check(bool *old_caps, bool *new_caps, Error **errp)
     if (new_caps[MIGRATION_CAPABILITY_BLOCK]) {
         error_setg(errp, "QEMU compiled without old-style (blk/-b, inc/-i) "
                    "block migration");
-        error_append_hint(errp, "Use drive_mirror+NBD instead.\n");
+        error_append_hint(errp, "Use blockdev-mirror with NBD instead.\n");
         return false;
     }
 #endif
+    if (new_caps[MIGRATION_CAPABILITY_BLOCK]) {
+        warn_report("block migration is deprecated;"
+                    " use blockdev-mirror with NBD instead");
+    }
 
 #ifndef CONFIG_REPLICATION
     if (new_caps[MIGRATION_CAPABILITY_X_COLO]) {
@@ -1386,6 +1391,8 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
     }
 
     if (params->has_block_incremental) {
+        warn_report("block migration is deprecated;"
+                    " use blockdev-mirror with NBD instead");
         s->parameters.block_incremental = params->block_incremental;
     }
     if (params->has_multifd_channels) {
-- 
2.41.0

[PATCH v8 5/5] migration: Deprecate old compression method

[Juan Quintela]

Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 docs/about/deprecated.rst |  8 +++++
 qapi/migration.json       | 63 ++++++++++++++++++++++++++-------------
 migration/options.c       | 13 ++++++++
 3 files changed, 64 insertions(+), 20 deletions(-)

diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 7ae872162d..e7f17827d3 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -488,3 +488,11 @@ devices or none.
 Please see "QMP invocation for live storage migration with
 ``blockdev-mirror`` + NBD" in docs/interop/live-block-operations.rst
 for a detailed explanation.
+
+old compression method (since 8.2)
+''''''''''''''''''''''''''''''''''
+
+Compression method fails too much.  Too many races.  We are going to
+remove it if nobody fixes it.  For starters, migration-test
+compression tests are disabled becase they fail randomly.  If you need
+compression, use multifd compression methods.
diff --git a/qapi/migration.json b/qapi/migration.json
index e3b00a215b..e6610af428 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -272,6 +272,10 @@
 # Features:
 #
 # @deprecated: Member @disk is deprecated because block migration is.
+#     Member @compression is deprecated because it is unreliable and
+#     untested.  It is recommended to use multifd migration, which
+#     offers an alternative compression implementation that is
+#     reliable and tested.
 #
 # Since: 0.14
 ##
@@ -289,7 +293,7 @@
            '*blocked-reasons': ['str'],
            '*postcopy-blocktime': 'uint32',
            '*postcopy-vcpu-blocktime': ['uint32'],
-           '*compression': 'CompressionStats',
+           '*compression': { 'type': 'CompressionStats', 'features': [ 'deprecated' ] },
            '*socket-address': ['SocketAddress'],
            '*dirty-limit-throttle-time-per-round': 'uint64',
            '*dirty-limit-ring-full-time': 'uint64'} }
@@ -530,7 +534,10 @@
 # Features:
 #
 # @deprecated: Member @block is deprecated.  Use blockdev-mirror with
-#     NBD instead.
+#     NBD instead.  Member @compression is deprecated because it is
+#     unreliable and untested.  It is recommended to use multifd
+#     migration, which offers an alternative compression
+#     implementation that is reliable and tested.
 #
 # @unstable: Members @x-colo and @x-ignore-shared are experimental.
 #
@@ -538,7 +545,8 @@
 ##
 { 'enum': 'MigrationCapability',
   'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks',
-           'compress', 'events', 'postcopy-ram',
+           { 'name': 'compress', 'features': [ 'deprecated' ] },
+           'events', 'postcopy-ram',
            { 'name': 'x-colo', 'features': [ 'unstable' ] },
            'release-ram',
            { 'name': 'block', 'features': [ 'deprecated' ] },
@@ -844,7 +852,9 @@
 # Features:
 #
 # @deprecated: Member @block-incremental is deprecated.  Use
-#     blockdev-mirror with NBD instead.
+#     blockdev-mirror with NBD instead.  Members @compress-level,
+#     @compress-threads, @decompress-threads and @compress-wait-thread
+#     are deprecated because @compression is deprecated.
 #
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
 #     are experimental.
@@ -854,8 +864,11 @@
 { 'enum': 'MigrationParameter',
   'data': ['announce-initial', 'announce-max',
            'announce-rounds', 'announce-step',
-           'compress-level', 'compress-threads', 'decompress-threads',
-           'compress-wait-thread', 'throttle-trigger-threshold',
+           { 'name': 'compress-level', 'features': [ 'deprecated' ] },
+           { 'name': 'compress-threads', 'features': [ 'deprecated' ] },
+           { 'name': 'decompress-threads', 'features': [ 'deprecated' ] },
+           { 'name': 'compress-wait-thread', 'features': [ 'deprecated' ] },
+           'throttle-trigger-threshold',
            'cpu-throttle-initial', 'cpu-throttle-increment',
            'cpu-throttle-tailslow',
            'tls-creds', 'tls-hostname', 'tls-authz', 'max-bandwidth',
@@ -1023,7 +1036,9 @@
 # Features:
 #
 # @deprecated: Member @block-incremental is deprecated.  Use
-#     blockdev-mirror with NBD instead.
+#     blockdev-mirror with NBD instead.  Members @compress-level,
+#     @compress-threads, @decompress-threads and @compress-wait-thread
+#     are deprecated because @compression is deprecated.
 #
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
 #     are experimental.
@@ -1038,10 +1053,14 @@
             '*announce-max': 'size',
             '*announce-rounds': 'size',
             '*announce-step': 'size',
-            '*compress-level': 'uint8',
-            '*compress-threads': 'uint8',
-            '*compress-wait-thread': 'bool',
-            '*decompress-threads': 'uint8',
+            '*compress-level': { 'type': 'uint8',
+                                 'features': [ 'deprecated' ] },
+            '*compress-threads':  { 'type': 'uint8',
+                                    'features': [ 'deprecated' ] },
+            '*compress-wait-thread':  { 'type': 'bool',
+                                        'features': [ 'deprecated' ] },
+            '*decompress-threads':  { 'type': 'uint8',
+                                      'features': [ 'deprecated' ] },
             '*throttle-trigger-threshold': 'uint8',
             '*cpu-throttle-initial': 'uint8',
             '*cpu-throttle-increment': 'uint8',
@@ -1078,7 +1097,7 @@
 # Example:
 #
 # -> { "execute": "migrate-set-parameters" ,
-#      "arguments": { "compress-level": 1 } }
+#      "arguments": { "multifd-channels": 5 } }
 # <- { "return": {} }
 ##
 { 'command': 'migrate-set-parameters', 'boxed': true,
@@ -1241,7 +1260,9 @@
 # Features:
 #
 # @deprecated: Member @block-incremental is deprecated.  Use
-#     blockdev-mirror with NBD instead.
+#     blockdev-mirror with NBD instead.  Members @compress-level,
+#     @compress-threads, @decompress-threads and @compress-wait-thread
+#     are deprecated because @compression is deprecated.
 #
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
 #     are experimental.
@@ -1253,10 +1274,14 @@
             '*announce-max': 'size',
             '*announce-rounds': 'size',
             '*announce-step': 'size',
-            '*compress-level': 'uint8',
-            '*compress-threads': 'uint8',
-            '*compress-wait-thread': 'bool',
-            '*decompress-threads': 'uint8',
+            '*compress-level': { 'type': 'uint8',
+                                 'features': [ 'deprecated' ] },
+            '*compress-threads': { 'type': 'uint8',
+                                   'features': [ 'deprecated' ] },
+            '*compress-wait-thread': { 'type': 'bool',
+                                       'features': [ 'deprecated' ] },
+            '*decompress-threads': { 'type': 'uint8',
+                                     'features': [ 'deprecated' ] },
             '*throttle-trigger-threshold': 'uint8',
             '*cpu-throttle-initial': 'uint8',
             '*cpu-throttle-increment': 'uint8',
@@ -1296,10 +1321,8 @@
 #
 # -> { "execute": "query-migrate-parameters" }
 # <- { "return": {
-#          "decompress-threads": 2,
+#          "multifd-channels": 2,
 #          "cpu-throttle-increment": 10,
-#          "compress-threads": 8,
-#          "compress-level": 1,
 #          "cpu-throttle-initial": 20,
 #          "max-bandwidth": 33554432,
 #          "downtime-limit": 300
diff --git a/migration/options.c b/migration/options.c
index a753eae438..b3514af9c3 100644
--- a/migration/options.c
+++ b/migration/options.c
@@ -483,6 +483,11 @@ bool migrate_caps_check(bool *old_caps, bool *new_caps, Error **errp)
                     " use blockdev-mirror with NBD instead");
     }
 
+    if (new_caps[MIGRATION_CAPABILITY_COMPRESS]) {
+        warn_report("old compression method is deprecated;"
+                    " use multifd compression methods instead");
+    }
+
 #ifndef CONFIG_REPLICATION
     if (new_caps[MIGRATION_CAPABILITY_X_COLO]) {
         error_setg(errp, "QEMU compiled without replication module"
@@ -1321,18 +1326,26 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
     /* TODO use QAPI_CLONE() instead of duplicating it inline */
 
     if (params->has_compress_level) {
+        warn_report("old compression is deprecated;"
+                    " use multifd compression methods instead");
         s->parameters.compress_level = params->compress_level;
     }
 
     if (params->has_compress_threads) {
+        warn_report("old compression is deprecated;"
+                    " use multifd compression methods instead");
         s->parameters.compress_threads = params->compress_threads;
     }
 
     if (params->has_compress_wait_thread) {
+        warn_report("old compression is deprecated;"
+                    " use multifd compression methods instead");
         s->parameters.compress_wait_thread = params->compress_wait_thread;
     }
 
     if (params->has_decompress_threads) {
+        warn_report("old compression is deprecated;"
+                    " use multifd compression methods instead");
         s->parameters.decompress_threads = params->decompress_threads;
     }
 
-- 
2.41.0