diff --git a/xo-alloc2/src/alloc2/CMakeLists.txt b/xo-alloc2/src/alloc2/CMakeLists.txt
index 07b7dec4..42e98ed4 100644
--- a/xo-alloc2/src/alloc2/CMakeLists.txt
+++ b/xo-alloc2/src/alloc2/CMakeLists.txt
@@ -11,3 +11,4 @@ set(SELF_SRCS
 xo_add_shared_library4(${SELF_LIB} ${PROJECT_NAME}Targets ${PROJECT_VERSION} 1 ${SELF_SRCS})
 # note: deps here must also appear in cmake/xo_alloc2Config.cmake.in
 xo_dependency(${SELF_LIB} xo_facet)
+xo_dependency(${SELF_LIB} indentlog)
diff --git a/xo-alloc2/src/alloc2/IAllocator_DArena.cpp b/xo-alloc2/src/alloc2/IAllocator_DArena.cpp
index babc0f00..83ebd8a2 100644
--- a/xo-alloc2/src/alloc2/IAllocator_DArena.cpp
+++ b/xo-alloc2/src/alloc2/IAllocator_DArena.cpp
@@ -5,6 +5,7 @@
 
 #include "IAllocator_DArena.hpp"
 #include "padding.hpp"
+#include "xo/indentlog/scope.hpp"
 #include <cassert>
 #include <cstddef>
 #include <sys/mman.h>
@@ -42,20 +43,21 @@ namespace xo {
         bool
         IAllocator_DArena::expand(DArena & s, size_t target_z)
         {
-//            scope log(XO_DEBUG(debug_flag_),
-//                      xtag("offset_z", offset_z),
-//                      xtag("committed_z", committed_z_));
+            scope log(XO_DEBUG(s.config_.debug_flag_),
+                      xtag("target_z", target_z),
+                      xtag("committed_z", s.committed_z_));
 
             if (target_z <= s.committed_z_) {
-//                log && log("trivial success, offset within committed range",
-//                           xtag("offset_z", offset_z),
-//                           xtag("committed_z", committed_z_));
+                log && log("trivial success, offset within committed range",
+                           xtag("target_z", target_z),
+                           xtag("committed_z", s.committed_z_));
                 return true;
             }
 
             if (s.lo_ + target_z > s.hi_) {
-//                throw std::runtime_error(tostr("ArenaAlloc::expand: requested size exceeds reserved size",
-//                                               xtag("requested", offset_z), xtag("reserved", reserved())));
+                throw std::runtime_error(tostr("ArenaAlloc::expand: requested size exceeds reserved size",
+                                               xtag("requested", target_z),
+                                               xtag("reserved", reserved(s))));
                 return false;
             }
 
diff --git a/xo-alloc2/utest/arena.test.cpp b/xo-alloc2/utest/arena.test.cpp
index 8e3cae61..72c6b4ec 100644
--- a/xo-alloc2/utest/arena.test.cpp
+++ b/xo-alloc2/utest/arena.test.cpp
@@ -10,6 +10,7 @@
 #include "xo/alloc2/IAllocator_DArena.hpp"
 #include "xo/alloc2/RAllocator.hpp"
 #include "xo/alloc2/padding.hpp"
+#include "xo/indentlog/scope.hpp"
 #include "xo/facet/obj.hpp"
 #include <catch2/catch.hpp>
 
@@ -20,6 +21,7 @@ namespace xo {
     using xo::mm::DArena;
     using xo::mm::ArenaConfig;
     using xo::facet::obj;
+    using xo::scope;
     using std::byte;
     using std::size_t;
 
@@ -107,13 +109,19 @@ namespace xo {
         {
             /* typed allocator a1o */
             ArenaConfig cfg { .name_ = "testarena",
-                              .size_ = 1 };
+                              .size_ = 1,
+                              .debug_flag_ = false };
             DArena arena = DArena::map(cfg);
             obj<AAllocator, DArena> a1o{&arena};
 
-            a1o.expand(3*1024*1024);
+            size_t z2 = 512;
+            REQUIRE(a1o.expand(z2));
 
             REQUIRE(a1o.reserved() % cfg.hugepage_z_ == 0);
+            REQUIRE(a1o.committed() >= z2);
+            REQUIRE(a1o.committed() % cfg.hugepage_z_ == 0);
+            /* .size() is synonym for .committed() */
+            REQUIRE(a1o.size() == a1o.committed());
 
 #ifdef NOPE
             byte * m = a1o.alloc(1);