diff --git a/php/ext/google/protobuf/php-upb.c b/php/ext/google/protobuf/php-upb.c
index ffa3075f12aaa..ebbe8c679e2e7 100644
--- a/php/ext/google/protobuf/php-upb.c
+++ b/php/ext/google/protobuf/php-upb.c
@@ -4571,9 +4571,10 @@ static upb_ArenaRoot _upb_Arena_FindRoot(upb_Arena* a) {
   return (upb_ArenaRoot){.root = ai, .tagged_count = poc};
 }
 
-size_t upb_Arena_SpaceAllocated(upb_Arena* arena) {
+size_t upb_Arena_SpaceAllocated(upb_Arena* arena, size_t* fused_count) {
   upb_ArenaInternal* ai = _upb_Arena_FindRoot(arena).root;
   size_t memsize = 0;
+  size_t local_fused_count = 0;
 
   while (ai != NULL) {
     upb_MemBlock* block = upb_Atomic_Load(&ai->blocks, memory_order_relaxed);
@@ -4582,8 +4583,10 @@ size_t upb_Arena_SpaceAllocated(upb_Arena* arena) {
       block = upb_Atomic_Load(&block->next, memory_order_relaxed);
     }
     ai = upb_Atomic_Load(&ai->next, memory_order_relaxed);
+    local_fused_count++;
   }
 
+  if (fused_count) *fused_count = local_fused_count;
   return memsize;
 }
 
diff --git a/php/ext/google/protobuf/php-upb.h b/php/ext/google/protobuf/php-upb.h
index 743a461e41447..70638f3bd68d4 100644
--- a/php/ext/google/protobuf/php-upb.h
+++ b/php/ext/google/protobuf/php-upb.h
@@ -347,7 +347,7 @@ void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
 
 // Must be last.
 
-#define _kUpb_Status_MaxMessage 127
+#define _kUpb_Status_MaxMessage 511
 
 typedef struct {
   bool ok;
@@ -778,7 +778,7 @@ UPB_API bool upb_Arena_Fuse(upb_Arena* a, upb_Arena* b);
 bool upb_Arena_IncRefFor(upb_Arena* a, const void* owner);
 void upb_Arena_DecRefFor(upb_Arena* a, const void* owner);
 
-size_t upb_Arena_SpaceAllocated(upb_Arena* a);
+size_t upb_Arena_SpaceAllocated(upb_Arena* a, size_t* fused_count);
 uint32_t upb_Arena_DebugRefCount(upb_Arena* a);
 
 UPB_API_INLINE upb_Arena* upb_Arena_New(void) {
diff --git a/ruby/ext/google/protobuf_c/ruby-upb.c b/ruby/ext/google/protobuf_c/ruby-upb.c
index 0fbb88d98c87a..4900b324c5ff0 100644
--- a/ruby/ext/google/protobuf_c/ruby-upb.c
+++ b/ruby/ext/google/protobuf_c/ruby-upb.c
@@ -4085,9 +4085,10 @@ static upb_ArenaRoot _upb_Arena_FindRoot(upb_Arena* a) {
   return (upb_ArenaRoot){.root = ai, .tagged_count = poc};
 }
 
-size_t upb_Arena_SpaceAllocated(upb_Arena* arena) {
+size_t upb_Arena_SpaceAllocated(upb_Arena* arena, size_t* fused_count) {
   upb_ArenaInternal* ai = _upb_Arena_FindRoot(arena).root;
   size_t memsize = 0;
+  size_t local_fused_count = 0;
 
   while (ai != NULL) {
     upb_MemBlock* block = upb_Atomic_Load(&ai->blocks, memory_order_relaxed);
@@ -4096,8 +4097,10 @@ size_t upb_Arena_SpaceAllocated(upb_Arena* arena) {
       block = upb_Atomic_Load(&block->next, memory_order_relaxed);
     }
     ai = upb_Atomic_Load(&ai->next, memory_order_relaxed);
+    local_fused_count++;
   }
 
+  if (fused_count) *fused_count = local_fused_count;
   return memsize;
 }
 
diff --git a/ruby/ext/google/protobuf_c/ruby-upb.h b/ruby/ext/google/protobuf_c/ruby-upb.h
index a784587e3494b..ea5cda26e6251 100755
--- a/ruby/ext/google/protobuf_c/ruby-upb.h
+++ b/ruby/ext/google/protobuf_c/ruby-upb.h
@@ -349,7 +349,7 @@ void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
 
 // Must be last.
 
-#define _kUpb_Status_MaxMessage 127
+#define _kUpb_Status_MaxMessage 511
 
 typedef struct {
   bool ok;
@@ -780,7 +780,7 @@ UPB_API bool upb_Arena_Fuse(upb_Arena* a, upb_Arena* b);
 bool upb_Arena_IncRefFor(upb_Arena* a, const void* owner);
 void upb_Arena_DecRefFor(upb_Arena* a, const void* owner);
 
-size_t upb_Arena_SpaceAllocated(upb_Arena* a);
+size_t upb_Arena_SpaceAllocated(upb_Arena* a, size_t* fused_count);
 uint32_t upb_Arena_DebugRefCount(upb_Arena* a);
 
 UPB_API_INLINE upb_Arena* upb_Arena_New(void) {