Document prepared statement compression properties.

trinodb · Feb 25, 2022 · 0e340de · 0e340de
1 parent 3345adb
commit 0e340de
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Showing 2 changed files with 23 additions and 3 deletions.
diff --git a/core/trino-main/src/main/java/io/trino/server/ProtocolConfig.java b/core/trino-main/src/main/java/io/trino/server/ProtocolConfig.java
@@ -49,7 +49,7 @@ public int getPreparedStatementCompressionThreshold()
     }
 
     @Config("protocol.v1.prepared-statement-compression.length-threshold")
-    @ConfigDescription("Prepared statements longer than the configured value will be compressed")
+    @ConfigDescription("Compression is applied to prepared statements longer than the configured value")
     public ProtocolConfig setPreparedStatementCompressionThreshold(int preparedStatementCompressionThreshold)
     {
         this.preparedStatementCompressionThreshold = preparedStatementCompressionThreshold;
@@ -63,7 +63,7 @@ public int getPreparedStatementCompressionMinimalGain()
     }
 
     @Config("protocol.v1.prepared-statement-compression.min-gain")
-    @ConfigDescription("Prepared statement compression will not be applied if size gain is less than the configured value")
+    @ConfigDescription("Prepared statement compression is not applied if the size gain is less than the configured value")
     public ProtocolConfig setPreparedStatementCompressionMinimalGain(int preparedStatementCompressionMinimalGain)
     {
         this.preparedStatementCompressionMinimalGain = preparedStatementCompressionMinimalGain;

diff --git a/docs/src/main/sphinx/admin/properties-general.rst b/docs/src/main/sphinx/admin/properties-general.rst
@@ -43,7 +43,7 @@ on a per-query basis using the ``redistribute_writes`` session property.
 **Type:** ``string``
 
 The 351 release of Trino changes the HTTP client protocol headers to start with
-``X-Trino-``. Clients for versions 350 and lower expect the HTTP headers to 
+``X-Trino-``. Clients for versions 350 and lower expect the HTTP headers to
 start with ``X-Presto-``, while newer clients expect ``X-Trino-``. You can support these
 older clients by setting this property to ``Presto``.
 
@@ -54,3 +54,23 @@ remove usage of this property.
 Ensure to use this only as a temporary measure to assist in your migration
 efforts.
 
+``protocol.v1.prepared-statement-compression.length-threshold``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+* **Type:** :ref:`prop-type-integer`
+* **Default value:** ``2048``
+
+Prepared statements that are submitted to Trino for processing, and are longer
+than the value of this property, are compressed for transport via the HTTP
+header to improve handling, and to avoid failures due to hitting HTTP header
+size limits.
+
+``protocol.v1.prepared-statement-compression.min-gain``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+* **Type:** :ref:`prop-type-integer`
+* **Default value:** ``512``
+
+Prepared statement compression is not applied if the size gain is less than the
+configured value. Smaller statements do not benefit from compression, and are
+left uncompressed.