add performance guidance for disabled config

Author: pellared

specification/logs/sdk.md

@@ -195,6 +195,8 @@ It consists of the following parameters:
   The value of `disabled` MUST be used to resolve whether a `Logger`
   is [Enabled](./api.md#enabled). If `disabled` is `true`, `Enabled`
   returns `false`. If `disabled` is `false`, `Enabled` returns `true`.
+  The access and synchronization of `disabled` should be implemented 
+  efficiently to minimize the performance overhead.
 
 ### Emit a LogRecord
 

specification/metrics/sdk.md

@@ -1011,6 +1011,9 @@ Note: If a user makes no configuration changes, `Enabled` returns `true` since b
 default `MeterConfig.disabled=false` and instruments use the default
 aggregation when no matching views match the instrument.
 
+The access and synchronization of `MeterConfig.disabled` should be implemented 
+efficiently to minimize the performance overhead.
+
 ## Attribute limits
 
 **Status**: [Stable](../document-status.md)

specification/trace/sdk.md

@@ -208,6 +208,8 @@ It consists of the following parameters:
   The value of `disabled` MUST be used to resolve whether a `Tracer`
   is [Enabled](./api.md#enabled). If `disabled` is `true`, `Enabled`
   returns `false`. If `disabled` is `false`, `Enabled` returns `true`.
+  The access and synchronization of `disabled` should be implemented 
+  efficiently to minimize the performance overhead.
 
 ### Enabled