diff --git a/indra/llmath/llvolume.cpp b/indra/llmath/llvolume.cpp
index 1ebd42babd..7c6a5a46c4 100644
--- a/indra/llmath/llvolume.cpp
+++ b/indra/llmath/llvolume.cpp
@@ -2403,7 +2403,27 @@ bool LLVolume::unpackVolumeFaces(std::istream& is, S32 size)
 		LL_DEBUGS("MeshStreaming") << "Failed to unzip LLSD blob for LoD with code " << uzip_result << " , will probably fetch from sim again." << LL_ENDL;
 		return false;
 	}
-	
+// <FS:Beq pp Rye> Add non-allocating variants of of unpackVolumeFaces
+	return unpackVolumeFacesInternal(mdl);
+}
+
+bool LLVolume::unpackVolumeFaces(U8* in_data, S32 size)
+{
+	//input stream is now pointing at a zlib compressed block of LLSD
+	//decompress block
+	LLSD mdl;
+	U32 uzip_result = LLUZipHelper::unzip_llsd(mdl, in_data, size);
+	if (uzip_result != LLUZipHelper::ZR_OK)
+	{
+		LL_DEBUGS("MeshStreaming") << "Failed to unzip LLSD blob for LoD with code " << uzip_result << " , will probably fetch from sim again." << LL_ENDL;
+		return false;
+	}
+	return unpackVolumeFacesInternal(mdl);
+}
+
+bool LLVolume::unpackVolumeFacesInternal(const LLSD& mdl)
+{
+// </FS:Beq pp Rye>
 	{
 		U32 face_count = mdl.size();
 
diff --git a/indra/llmath/llvolume.h b/indra/llmath/llvolume.h
index c9b12a9e97..c745a202db 100644
--- a/indra/llmath/llvolume.h
+++ b/indra/llmath/llvolume.h
@@ -1099,7 +1099,13 @@ protected:
 	void createVolumeFaces();
 public:
 	virtual bool unpackVolumeFaces(std::istream& is, S32 size);
+// <FS:Beq pp Rye> Add non-allocating variants of of unpackVolumeFaces
+	bool unpackVolumeFaces(U8* in_data, S32 size);
+private:
+	bool unpackVolumeFacesInternal(const LLSD& mdl);
 
+public:
+// </FS:Beq pp Rye>
 	virtual void setMeshAssetLoaded(BOOL loaded);
 	virtual BOOL isMeshAssetLoaded();
 
diff --git a/indra/newview/lldrawable.cpp b/indra/newview/lldrawable.cpp
index 68d5c53b80..d7ebf28354 100644
--- a/indra/newview/lldrawable.cpp
+++ b/indra/newview/lldrawable.cpp
@@ -918,9 +918,15 @@ void LLDrawable::updateDistance(LLCamera& camera, bool force_update)
             // MAINT-7926 Handle volumes in an animated object as a special case
             // SL-937: add dynamic box handling for rigged mesh on regular avatars.
             //if (volume->getAvatar() && volume->getAvatar()->isControlAvatar())
-            if (volume->getAvatar())
+            // <FS:Beq pp Rye> reduce recursive calls.
+            // if (volume->getAvatar())
+            // {
+            //     const LLVector3* av_box = volume->getAvatar()->getLastAnimExtents();
+            LLVOAvatar* avatarp = volume->getAvatar();
+            if (avatarp)
             {
-                const LLVector3* av_box = volume->getAvatar()->getLastAnimExtents();
+                const LLVector3* av_box = avatarp->getLastAnimExtents();
+            // </FS:Beq pp Rye>
                 LLVector3 cam_pos_from_agent = LLViewerCamera::getInstance()->getOrigin();
                 LLVector3 cam_to_box_offset = point_to_box_offset(cam_pos_from_agent, av_box);
                 mDistanceWRTCamera = llmax(0.01f, ll_round(cam_to_box_offset.magVec(), 0.01f));
diff --git a/indra/newview/llmaterialmgr.cpp b/indra/newview/llmaterialmgr.cpp
index 099fdadd86..f5218ee4c6 100644
--- a/indra/newview/llmaterialmgr.cpp
+++ b/indra/newview/llmaterialmgr.cpp
@@ -477,7 +477,10 @@ void LLMaterialMgr::onGetAllResponse(bool success, const LLSD& content, const LL
 	std::istringstream content_stream(content_string);
 
 	LLSD response_data;
-	U32 uzip_result = LLUZipHelper::unzip_llsd(response_data, content_stream, content_binary.size());
+	// <FS:Beq pp Rye> Use new variant unzip_llsd
+	// U32 uzip_result = LLUZipHelper::unzip_llsd(response_data, content_stream, content_binary.size());
+	U32 uzip_result = LLUZipHelper::unzip_llsd(response_data, content_binary.data(), content_binary.size());
+	// </FS:Beq pp Rye>
 	if (uzip_result != LLUZipHelper::ZR_OK)
 	{
 		LL_WARNS("Materials") << "Cannot unzip LLSD binary content: " << uzip_result << LL_ENDL;
diff --git a/indra/newview/llmeshrepository.cpp b/indra/newview/llmeshrepository.cpp
index fc9b5174d7..0f1dc1b1da 100644
--- a/indra/newview/llmeshrepository.cpp
+++ b/indra/newview/llmeshrepository.cpp
@@ -78,6 +78,10 @@
 #include "llfloaterreg.h"
 
 #include "boost/lexical_cast.hpp"
+// <FS:Beq pp Rye> Reduce temporaries and copes in decoding mesh headers
+#include <boost/iostreams/device/array.hpp>
+#include <boost/iostreams/stream.hpp>
+// </FS:Beq pp Rye>
 
 #ifndef LL_WINDOWS
 #include "netdb.h"
@@ -1901,27 +1905,35 @@ EMeshProcessingResult LLMeshRepoThread::headerReceived(const LLVolumeParams& mes
 	U32 header_size = 0;
 	if (data_size > 0)
 	{
-        std::istringstream stream;
-        try
-        {
-            std::string res_str((char*)data, data_size);
+		// <FS:Beq pp Rye> Reduce temporaries and copes in decoding mesh headers
+        // std::istringstream stream;
+        // try
+        // {
+        //     std::string res_str((char*)data, data_size);
 
-            std::string deprecated_header("<? LLSD/Binary ?>");
+        //     std::string deprecated_header("<? LLSD/Binary ?>");
 
-            if (res_str.substr(0, deprecated_header.size()) == deprecated_header)
-            {
-                res_str = res_str.substr(deprecated_header.size() + 1, data_size);
-                header_size = deprecated_header.size() + 1;
-            }
-            data_size = res_str.size();
+        //     if (res_str.substr(0, deprecated_header.size()) == deprecated_header)
+        //     {
+        //         res_str = res_str.substr(deprecated_header.size() + 1, data_size);
+        //         header_size = deprecated_header.size() + 1;
+        //     }
+        //     data_size = res_str.size();
 
-            stream.str(res_str);
-        }
-        catch (std::bad_alloc&)
-        {
-            // out of memory, we won't be able to process this mesh
-            return MESH_OUT_OF_MEMORY;
-        }
+        //     stream.str(res_str);
+        // }
+        // catch (std::bad_alloc&)
+        // {
+        //     // out of memory, we won't be able to process this mesh
+        //     return MESH_OUT_OF_MEMORY;
+        // }
+		U32 dsize = data_size;
+		char* result_ptr = strip_deprecated_header((char*)data, dsize, &header_size);
+
+		data_size = dsize;
+
+		boost::iostreams::stream<boost::iostreams::array_source> stream(result_ptr, data_size);
+		// </FS:Beq pp Rye> 
 
 		if (!LLSDSerialize::fromBinary(header, stream, data_size))
 		{
@@ -1990,19 +2002,22 @@ EMeshProcessingResult LLMeshRepoThread::lodReceived(const LLVolumeParams& mesh_p
 	}
 
 	LLPointer<LLVolume> volume = new LLVolume(mesh_params, LLVolumeLODGroup::getVolumeScaleFromDetail(lod));
-	std::istringstream stream;
-	try
-	{
-		std::string mesh_string((char*)data, data_size);
-		stream.str(mesh_string);
-	}
-	catch (std::bad_alloc&)
-	{
-		// out of memory, we won't be able to process this mesh
-		return MESH_OUT_OF_MEMORY;
-	}
+	// <FS:Beq pp Rye> Reduce temporaries and copes in decoding mesh headers
+	// std::istringstream stream;
+	// try
+	// {
+	// 	std::string mesh_string((char*)data, data_size);
+	// 	stream.str(mesh_string);
+	// }
+	// catch (std::bad_alloc&)
+	// {
+	// 	// out of memory, we won't be able to process this mesh
+	// 	return MESH_OUT_OF_MEMORY;
+	// }
 
-	if (volume->unpackVolumeFaces(stream, data_size))
+	// if (volume->unpackVolumeFaces(stream, data_size))
+	if (volume->unpackVolumeFaces(data, data_size))
+	// </FS:Beq pp Rye>
 	{
 		if (volume->getNumFaces() > 0)
 		{
@@ -2032,10 +2047,13 @@ bool LLMeshRepoThread::skinInfoReceived(const LLUUID& mesh_id, U8* data, S32 dat
 	{
         try
         {
-            std::string res_str((char*)data, data_size);
-            std::istringstream stream(res_str);
+            // <FS:Beq pp Rye> Reduce temporaries and copes in decoding mesh headers
+            // std::string res_str((char*)data, data_size);
+            // std::istringstream stream(res_str);
 
-            U32 uzip_result = LLUZipHelper::unzip_llsd(skin, stream, data_size);
+            // U32 uzip_result = LLUZipHelper::unzip_llsd(skin, stream, data_size);
+            U32 uzip_result = LLUZipHelper::unzip_llsd(skin, data, data_size);
+            // </FS:Beq pp Rye>
             if (uzip_result != LLUZipHelper::ZR_OK)
             {
                 LL_WARNS(LOG_MESH) << "Mesh skin info parse error.  Not a valid mesh asset!  ID:  " << mesh_id
@@ -2073,10 +2091,13 @@ bool LLMeshRepoThread::decompositionReceived(const LLUUID& mesh_id, U8* data, S3
     {
         try
         {
-            std::string res_str((char*)data, data_size);
-            std::istringstream stream(res_str);
+            // <FS:Beq pp Rye> Reduce temporaries and copes in decoding mesh headers
+            // std::string res_str((char*)data, data_size);
+            // std::istringstream stream(res_str);
 
-            U32 uzip_result = LLUZipHelper::unzip_llsd(decomp, stream, data_size);
+            // U32 uzip_result = LLUZipHelper::unzip_llsd(decomp, stream, data_size);
+            U32 uzip_result = LLUZipHelper::unzip_llsd(decomp, data, data_size);
+            // <FS:Beq pp Rye>
             if (uzip_result != LLUZipHelper::ZR_OK)
             {
                 LL_WARNS(LOG_MESH) << "Mesh decomposition parse error.  Not a valid mesh asset!  ID:  " << mesh_id
@@ -2085,7 +2106,7 @@ bool LLMeshRepoThread::decompositionReceived(const LLUUID& mesh_id, U8* data, S3
                 return false;
             }
         }
-        catch (std::bad_alloc&)
+        catch (const std::bad_alloc&) // <FS:Beq pp Rye/> const cos const!
         {
             LL_WARNS(LOG_MESH) << "Out of memory for mesh ID " << mesh_id << " of size: " << data_size << LL_ENDL;
             return false;
@@ -2122,20 +2143,22 @@ EMeshProcessingResult LLMeshRepoThread::physicsShapeReceived(const LLUUID& mesh_
 		volume_params.setSculptID(mesh_id, LL_SCULPT_TYPE_MESH);
 		LLPointer<LLVolume> volume = new LLVolume(volume_params,0);
 
-        std::istringstream stream;
-        try
-        {
-            std::string mesh_string((char*)data, data_size);
-            stream.str(mesh_string);
-        }
-        catch (std::bad_alloc&)
-        {
-            // out of memory, we won't be able to process this mesh
-            delete d;
-            return MESH_OUT_OF_MEMORY;
-        }
+		// <FS:Beq pp Rye> Reduce temporaries and copes in decoding mesh headers
+        // std::istringstream stream;
+        // try
+        // {
+        //     std::string mesh_string((char*)data, data_size);
+        //     stream.str(mesh_string);
+        // }
+        // catch (std::bad_alloc&)
+        // {
+        //     // out of memory, we won't be able to process this mesh
+        //     delete d;
+        //     return MESH_OUT_OF_MEMORY;
+        // }
 
-		if (volume->unpackVolumeFaces(stream, data_size))
+		// if (volume->unpackVolumeFaces(stream, data_size))
+		if (volume->unpackVolumeFaces(data, data_size))
 		{
 			//load volume faces into decomposition buffer
 			S32 vertex_count = 0;
diff --git a/indra/newview/llpathfindingnavmesh.cpp b/indra/newview/llpathfindingnavmesh.cpp
index 0287c07f96..41976674a7 100644
--- a/indra/newview/llpathfindingnavmesh.cpp
+++ b/indra/newview/llpathfindingnavmesh.cpp
@@ -140,12 +140,17 @@ void LLPathfindingNavMesh::handleNavMeshResult(const LLSD &pContent, U32 pNavMes
 		if ( pContent.has(NAVMESH_DATA_FIELD) )
 		{
 			const LLSD::Binary &value = pContent.get(NAVMESH_DATA_FIELD).asBinary();
-			unsigned int binSize = value.size();
-			std::string newStr(reinterpret_cast<const char *>(&value[0]), binSize);
-			std::istringstream streamdecomp( newStr );
+			// <FS:Beq pp Rye> Use new variants of unzip_llsd calls
+			// unsigned int binSize = value.size();
+			// std::string newStr(reinterpret_cast<const char *>(&value[0]), binSize);
+			// std::istringstream streamdecomp( newStr );
+			// </FS:Beq pp Rye> 
 			unsigned int decompBinSize = 0;
 			bool valid = false;
-			U8* pUncompressedNavMeshContainer = unzip_llsdNavMesh( valid, decompBinSize, streamdecomp, binSize ) ;
+			// <FS:Beq pp Rye> Use new variants of unzip_llsd calls
+			// U8* pUncompressedNavMeshContainer = unzip_llsdNavMesh( valid, decompBinSize, streamdecomp, binSize ) ;
+			U8* pUncompressedNavMeshContainer = unzip_llsdNavMesh( valid, decompBinSize, value.data(), value.size() ) ;
+			// </FS:Beq pp Rye> 
 			if ( !valid )
 			{
 				LL_WARNS() << "Unable to decompress the navmesh llsd." << LL_ENDL;