add to release notes

Signed-off-by: deepthi <deepthi@planetscale.com>

changelog/16.0/16.0.0/release_notes.md

@@ -5,6 +5,7 @@
 
 - **[Known Issues](#known-issues)**
   - [MySQL & Xtrabackup known issue](#mysql-xtrabackup-ddl)
+  - [VTTablet Restore Metrics](#vttablet-restore-metrics)
 - **[Major Changes](#major-changes)**
   - **[Breaking Changes](#breaking-changes)**
     - [VTGate Advertised MySQL Version](#advertised-mysql-version)
@@ -100,6 +101,11 @@ or
 > ALTER TABLE your_table ENGINE=InnoDB;
 ```
 
+#### <a id="vttablet-restore-metrics">VTTablet Restore Metrics
+
+As part of the VTTablet Sidecar Schema Maintenance Refactor in v16.0.0, we dropped the `local_metadata` table from the sidecar database schema. This table was storing a couple of metrics related to restores from backup, which have now been lost.
+They have been re-introduced in v17.0.0 as metrics that can be accessed from `/debug/vars`.
+
 ## <a id="major-changes"/>Major Changes
 
 ### <a id="breaking-changes"/>Breaking Changes

changelog/17.0/17.0.0/release_notes.md

@@ -12,6 +12,7 @@
     - [Shard name validation in TopoServer](#shard-name-validation)
     - [Compression CLI flags removed from vtctld and vtctldclient binaries](#remove-compression-flags-from-vtctld-binaries)
     - [VtctldClient command RestoreFromBackup will now use the correct context](#VtctldClient-RestoreFromBackup)
+    - [VTTablet Restore Metrics](#vttablet-restore-metrics)
   - **[New command line flags and behavior](#new-flag)**
     - [Builtin backup: read buffering flags](#builtin-backup-read-buffering-flags)
     - [Manifest backup external decompressor command](#manifest-backup-external-decompressor-command)
@@ -132,6 +133,11 @@ Prior to v17, this asynchronous process could run indefinitely in the background
 this behavior was changed to use a context with a timeout of `action_timeout`. If you are using VtctldClient to initiate a restore, make sure you provide an appropriate value for action_timeout to give enough
 time for the restore process to complete. Otherwise, the restore will throw an error if the context expires before it completes.
 
+#### <a id="vttablet-restore-metrics">VTTablet Restore Metrics
+
+As part of the VTTablet Sidecar Schema Maintenance Refactor in v16.0.0, we dropped the `local_metadata` table from the sidecar database schema. This table was storing a couple of metrics related to restores from backup.
+They have now been re-introduced as metrics that can be accessed from `/debug/vars`.
+
 ### <a id="Vttablet-TxThrottler">Vttablet's transaction throttler now also throttles DML outside of `BEGIN; ...; COMMIT;` blocks
 
 Prior to v17, `vttablet`'s transaction throttler (enabled with `--enable-tx-throttler`) would only throttle requests done inside an explicit transaction, i.e., a `BEGIN; ...; COMMIT;` block.