diff --git a/qmp-commands.hx b/qmp-commands.hx
index de896a5..e0e519a 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1107,7 +1107,10 @@ Arguments:
                   obvious choice.  Care should be taken when specifying the
                   string, to specify a valid filename or protocol.
                   (json-string, optional) (Since 2.1)
-- "speed":  the maximum speed, in bytes per second (json-int, optional)
+- "speed": The maximum speed, in bytes per second. Note: In the current
+           implementation, at least 5MiB/s will be written, even if a lower
+           speed has been set. This will be fixed in the future. (json-int,
+           optional)
 - "on-error": the action to take on an error (default 'report').  'stop' and
               'enospc' can only be used if the block device supports io-status.
               (json-string, optional) (Since 2.1)
@@ -1172,7 +1175,10 @@ Arguments:
           size of the smaller top, you can safely truncate it
           yourself once the commit operation successfully completes.
           (json-string)
-- "speed":  the maximum speed, in bytes per second (json-int, optional)
+- "speed": The maximum speed, in bytes per second. Note: In the current
+           implementation, at least 5MiB/s will be written, even if a lower
+           speed has been set. This will be fixed in the future. (json-int,
+           optional)
 
 
 Example:
@@ -1219,7 +1225,10 @@ Arguments:
             is "incremental", must NOT be present otherwise.
 - "mode": whether and how QEMU should create a new image
           (NewImageMode, optional, default 'absolute-paths')
-- "speed": the maximum speed, in bytes per second (json-int, optional)
+- "speed": The maximum speed, in bytes per second. Note: The current
+           implementation will write at a minimum speed that depends on device
+           and format, even if a lower speed is configured. This will be fixed
+           in the future. (json-int, optional)
 - "on-source-error": the action to take on an error on the source, default
                      'report'.  'stop' and 'enospc' can only be used
                      if the block device supports io-status.
@@ -1260,7 +1269,10 @@ Arguments:
           possibilities include "full" for all the disk, "top" for only the
           sectors allocated in the topmost image, or "none" to only replicate
           new I/O (MirrorSyncMode).
-- "speed": the maximum speed, in bytes per second (json-int, optional)
+- "speed": The maximum speed, in bytes per second. Note: The current
+           implementation will write at a minimum speed that depends on device
+           and format, even if a lower speed is configured. This will be fixed
+           in the future. (json-int, optional)
 - "on-source-error": the action to take on an error on the source, default
                      'report'.  'stop' and 'enospc' can only be used
                      if the block device supports io-status.
@@ -1659,8 +1671,12 @@ Arguments:
               (json-string, optional)
 - "mode": how an image file should be created into the target
   file/device (NewImageMode, optional, default 'absolute-paths')
-- "speed": maximum speed of the streaming job, in bytes per second
-  (json-int)
+- "speed": The maximum speed, in bytes per second. Note: In the
+           current implementation, the buffer will be written at least
+           once per 100ms. So with the default buffer size of 10MiB,
+           at least 10MiB/s will be written, even if a lower speed is
+           configured. This will be fixed in the future. (json-int,
+           optional)
 - "granularity": granularity of the dirty bitmap, in bytes (json-int, optional)
 - "buf-size": maximum amount of data in flight from source to target, in bytes
   (json-int, default 10M)
@@ -1712,8 +1728,12 @@ Arguments:
 - "target": device name to mirror to (json-string)
 - "replaces": the block driver node name to replace when finished
               (json-string, optional)
-- "speed": maximum speed of the streaming job, in bytes per second
-  (json-int)
+- "speed": The maximum speed, in bytes per second. Note: In the
+           current implementation, the buffer will be written at least
+           once per 100ms. So with the default buffer size of 10MiB,
+           at least 10MiB/s will be written, even if a lower speed is
+           configured. This will be fixed in the future. (json-int,
+           optional)
 - "granularity": granularity of the dirty bitmap, in bytes (json-int, optional)
 - "buf_size": maximum amount of data in flight from source to target, in bytes
   (json-int, default 10M)
