diff --git a/src/api-env.c b/src/api-env.c
index 852d3394..4aa7bd2e 100644
--- a/src/api-env.c
+++ b/src/api-env.c
@@ -530,12 +530,7 @@ __cold int mdbx_env_openW(MDBX_env *env, const wchar_t *pathname,
         base + bitmap_bytes +
         env->max_dbi * (sizeof(txn->dbs[0]) + sizeof(txn->cursors[0]) +
                         sizeof(txn->dbi_seqs[0]) + sizeof(txn->dbi_state[0]));
-    rc = env_page_auxbuffer(env);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto bailout;
 
-    memset(env->page_auxbuf, -1, env->ps * (size_t)2);
-    memset(ptr_disp(env->page_auxbuf, env->ps * (size_t)2), 0, env->ps);
     txn = osal_calloc(1, size);
     if (unlikely(!txn)) {
       rc = MDBX_ENOMEM;
diff --git a/src/dxb.c b/src/dxb.c
index 401115d9..c91880fe 100644
--- a/src/dxb.c
+++ b/src/dxb.c
@@ -641,6 +641,12 @@ __cold int dxb_setup(MDBX_env *env, const int lck_rc,
 
   if (env->ps != header.pagesize)
     env_setup_pagesize(env, header.pagesize);
+  if ((env->flags & MDBX_RDONLY) == 0) {
+    err = env_page_auxbuffer(env);
+    if (unlikely(err != MDBX_SUCCESS))
+      return err;
+  }
+
   const size_t used_bytes = pgno2bytes(env, header.geometry.first_unallocated);
   const size_t used_aligned2os_bytes =
       ceil_powerof2(used_bytes, globals.sys_pagesize);
diff --git a/src/env.c b/src/env.c
index 2d5dadc5..c4902765 100644
--- a/src/env.c
+++ b/src/env.c
@@ -10,10 +10,16 @@ bool env_txn0_owned(const MDBX_env *env) {
 }
 
 int env_page_auxbuffer(MDBX_env *env) {
-  return env->page_auxbuf ? MDBX_SUCCESS
-                          : osal_memalign_alloc(globals.sys_pagesize,
-                                                env->ps * (size_t)NUM_METAS,
-                                                &env->page_auxbuf);
+  const int err =
+      env->page_auxbuf
+          ? MDBX_SUCCESS
+          : osal_memalign_alloc(globals.sys_pagesize,
+                                env->ps * (size_t)NUM_METAS, &env->page_auxbuf);
+  if (likely(err == MDBX_SUCCESS)) {
+    memset(env->page_auxbuf, -1, env->ps * (size_t)2);
+    memset(ptr_disp(env->page_auxbuf, env->ps * (size_t)2), 0, env->ps);
+  }
+  return err;
 }
 
 __cold unsigned env_setup_pagesize(MDBX_env *env, const size_t pagesize) {
@@ -22,11 +28,8 @@ __cold unsigned env_setup_pagesize(MDBX_env *env, const size_t pagesize) {
   ENSURE(env, is_powerof2(pagesize));
   ENSURE(env, pagesize >= MDBX_MIN_PAGESIZE);
   ENSURE(env, pagesize <= MDBX_MAX_PAGESIZE);
+  ENSURE(env, !env->page_auxbuf && env->ps != pagesize);
   env->ps = (unsigned)pagesize;
-  if (env->page_auxbuf) {
-    osal_memalign_free(env->page_auxbuf);
-    env->page_auxbuf = nullptr;
-  }
 
   STATIC_ASSERT(MAX_GC1OVPAGE(MDBX_MIN_PAGESIZE) > 4);
   STATIC_ASSERT(MAX_GC1OVPAGE(MDBX_MAX_PAGESIZE) < PAGELIST_LIMIT);
diff --git a/src/meta.c b/src/meta.c
index ee2a5aef..7214335b 100644
--- a/src/meta.c
+++ b/src/meta.c
@@ -392,9 +392,6 @@ __cold meta_t *meta_init_triplet(const MDBX_env *env, void *buffer) {
 __cold int __must_check_result meta_override(MDBX_env *env, size_t target,
                                              txnid_t txnid,
                                              const meta_t *shape) {
-  int rc = env_page_auxbuffer(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
   page_t *const page = env->page_auxbuf;
   meta_model(env, page, target,
              &((target == 0 && shape) ? shape : METAPAGE(env, 0))->dxbid);
@@ -440,7 +437,7 @@ __cold int __must_check_result meta_override(MDBX_env *env, size_t target,
   }
 
   meta_sign_as_steady(model);
-  rc = meta_validate(env, model, page, (pgno_t)target, nullptr);
+  int rc = meta_validate(env, model, page, (pgno_t)target, nullptr);
   if (unlikely(MDBX_IS_ERROR(rc)))
     return MDBX_PROBLEM;