Add trace logging for the POV size (#294)

* Add trace logging for the POV size

* :(

cumulus/collator/src/lib.rs

@@ -573,6 +573,14 @@ where
 			return None;
 		}
 
+		trace!(
+			target: "cumulus-collator",
+			"PoV size {{ header: {}kb, extrinsics: {}kb, storage_proof: {}kb }}",
+			b.header().encode().len() as f64 / 1024f64,
+			b.extrinsics().encode().len() as f64 / 1024f64,
+			b.storage_proof().encode().len() as f64 / 1024f64,
+		);
+
 		let collation =
 			self.build_collation(b, block_hash, validation_data.persisted.block_number)?;
 		let pov_hash = collation.proof_of_validity.hash();

cumulus/runtime/src/lib.rs

@@ -41,6 +41,7 @@ pub struct ParachainBlockData<B: BlockT> {
 }
 
 impl<B: BlockT> ParachainBlockData<B> {
+	/// Creates a new instance of `Self`.
 	pub fn new(
 		header: <B as BlockT>::Header,
 		extrinsics: Vec<<B as BlockT>::Extrinsic>,
@@ -67,4 +68,9 @@ impl<B: BlockT> ParachainBlockData<B> {
 	pub fn extrinsics(&self) -> &[B::Extrinsic] {
 		&self.extrinsics
 	}
+
+	/// Returns the [`StorageProof`].
+	pub fn storage_proof(&self) -> &StorageProof {
+		&self.storage_proof
+	}
 }