diff --git a/src/api-txn.c b/src/api-txn.c
index ab5d4df4..d75f05ff 100644
--- a/src/api-txn.c
+++ b/src/api-txn.c
@@ -40,13 +40,14 @@ int mdbx_txn_straggler(const MDBX_txn *txn, int *percent)
 
 __cold int mdbx_dbi_dupsort_depthmask(const MDBX_txn *txn, MDBX_dbi dbi,
                                       uint32_t *mask) {
+  if (unlikely(!mask))
+    return LOG_IFERR(MDBX_EINVAL);
+
+  *mask = 0;
   int rc = check_txn(txn, MDBX_TXN_BLOCKED);
   if (unlikely(rc != MDBX_SUCCESS))
     return LOG_IFERR(rc);
 
-  if (unlikely(!mask))
-    return LOG_IFERR(MDBX_EINVAL);
-
   cursor_couple_t cx;
   rc = cursor_init(&cx.outer, txn, dbi);
   if (unlikely(rc != MDBX_SUCCESS))
@@ -56,7 +57,6 @@ __cold int mdbx_dbi_dupsort_depthmask(const MDBX_txn *txn, MDBX_dbi dbi,
 
   MDBX_val key, data;
   rc = outer_first(&cx.outer, &key, &data);
-  *mask = 0;
   while (rc == MDBX_SUCCESS) {
     const node_t *node =
         page_node(cx.outer.pg[cx.outer.top], cx.outer.ki[cx.outer.top]);
@@ -88,13 +88,15 @@ __cold int mdbx_dbi_dupsort_depthmask(const MDBX_txn *txn, MDBX_dbi dbi,
 }
 
 int mdbx_canary_get(const MDBX_txn *txn, MDBX_canary *canary) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return LOG_IFERR(rc);
-
   if (unlikely(canary == nullptr))
     return LOG_IFERR(MDBX_EINVAL);
 
+  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
+  if (unlikely(rc != MDBX_SUCCESS)) {
+    memset(canary, 0, sizeof(*canary));
+    return LOG_IFERR(rc);
+  }
+
   *canary = txn->canary;
   return MDBX_SUCCESS;
 }
diff --git a/src/cold.c b/src/cold.c
index db3b0b87..53f0a6a0 100644
--- a/src/cold.c
+++ b/src/cold.c
@@ -554,13 +554,15 @@ __cold int mdbx_env_set_flags(MDBX_env *env, MDBX_env_flags_t flags,
 }
 
 __cold int mdbx_env_get_flags(const MDBX_env *env, unsigned *arg) {
-  int rc = check_env(env, false);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return LOG_IFERR(rc);
-
   if (unlikely(!arg))
     return LOG_IFERR(MDBX_EINVAL);
 
+  int rc = check_env(env, false);
+  if (unlikely(rc != MDBX_SUCCESS)) {
+    *arg = 0;
+    return LOG_IFERR(rc);
+  }
+
   *arg = env->flags & ENV_USABLE_FLAGS;
   return MDBX_SUCCESS;
 }
diff --git a/src/dbi.c b/src/dbi.c
index 109198d5..888f0e03 100644
--- a/src/dbi.c
+++ b/src/dbi.c
@@ -908,21 +908,26 @@ int mdbx_dbi_close(MDBX_env *env, MDBX_dbi dbi) {
 
 int mdbx_dbi_flags_ex(const MDBX_txn *txn, MDBX_dbi dbi, unsigned *flags,
                       unsigned *state) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED - MDBX_TXN_ERROR - MDBX_TXN_PARKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return LOG_IFERR(rc);
-
   if (unlikely(!flags || !state))
     return LOG_IFERR(MDBX_EINVAL);
 
-  rc = dbi_check(txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
+  int rc = check_txn(txn, MDBX_TXN_BLOCKED - MDBX_TXN_ERROR - MDBX_TXN_PARKED);
+  if (unlikely(rc != MDBX_SUCCESS)) {
+    *flags = 0;
+    *state = 0;
     return LOG_IFERR(rc);
+  }
+
+  rc = dbi_check(txn, dbi);
+  if (unlikely(rc != MDBX_SUCCESS)) {
+    *flags = 0;
+    *state = 0;
+    return LOG_IFERR(rc);
+  }
 
   *flags = txn->dbs[dbi].flags & DB_PERSISTENT_FLAGS;
   *state =
       txn->dbi_state[dbi] & (DBI_FRESH | DBI_CREAT | DBI_DIRTY | DBI_STALE);
-
   return MDBX_SUCCESS;
 }
 
@@ -968,33 +973,41 @@ static void stat_get(const tree_t *db, MDBX_stat *st, size_t bytes) {
 
 __cold int mdbx_dbi_stat(const MDBX_txn *txn, MDBX_dbi dbi, MDBX_stat *dest,
                          size_t bytes) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return LOG_IFERR(rc);
-
   if (unlikely(!dest))
     return LOG_IFERR(MDBX_EINVAL);
 
+  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
+  if (unlikely(rc != MDBX_SUCCESS))
+    goto bailout;
+
   rc = dbi_check(txn, dbi);
   if (unlikely(rc != MDBX_SUCCESS))
-    return LOG_IFERR(rc);
+    goto bailout;
 
   const size_t size_before_modtxnid = offsetof(MDBX_stat, ms_mod_txnid);
-  if (unlikely(bytes != sizeof(MDBX_stat)) && bytes != size_before_modtxnid)
-    return LOG_IFERR(MDBX_EINVAL);
+  if (unlikely(bytes != sizeof(MDBX_stat)) && bytes != size_before_modtxnid) {
+    rc = MDBX_EINVAL;
+    goto bailout;
+  }
 
-  if (unlikely(txn->flags & MDBX_TXN_BLOCKED))
-    return LOG_IFERR(MDBX_BAD_TXN);
+  if (unlikely(txn->flags & MDBX_TXN_BLOCKED)) {
+    rc = MDBX_BAD_TXN;
+    goto bailout;
+  }
 
   if (unlikely(txn->dbi_state[dbi] & DBI_STALE)) {
     rc = tbl_fetch((MDBX_txn *)txn, dbi);
     if (unlikely(rc != MDBX_SUCCESS))
-      return LOG_IFERR(rc);
+      goto bailout;
   }
 
   dest->ms_psize = txn->env->ps;
   stat_get(&txn->dbs[dbi], dest, bytes);
   return MDBX_SUCCESS;
+
+bailout:
+  memset(dest, 0, bytes);
+  return LOG_IFERR(rc);
 }
 
 __cold const tree_t *dbi_dig(const MDBX_txn *txn, const size_t dbi,
diff --git a/src/logging_and_debug.c b/src/logging_and_debug.c
index 0fc4098a..20d8419e 100644
--- a/src/logging_and_debug.c
+++ b/src/logging_and_debug.c
@@ -61,7 +61,9 @@ __cold void debug_log(int level, const char *function, int line,
 
 __cold int log_error(const int err, const char *func, unsigned line) {
   assert(err != MDBX_SUCCESS);
-  if (unlikely(globals.loglevel >= MDBX_LOG_DEBUG)) {
+  if (unlikely(globals.loglevel >= MDBX_LOG_DEBUG) &&
+      (globals.loglevel >= MDBX_LOG_TRACE ||
+       !(err == MDBX_RESULT_TRUE || err == MDBX_NOTFOUND))) {
     char buf[256];
     debug_log(MDBX_LOG_ERROR, func, line, "error %d (%s)\n", err,
               mdbx_strerror_r(err, buf, sizeof(buf)));
diff --git a/src/logging_and_debug.h b/src/logging_and_debug.h
index 6b9ef145..b3cef271 100644
--- a/src/logging_and_debug.h
+++ b/src/logging_and_debug.h
@@ -161,8 +161,25 @@ MDBX_INTERNAL const char *pagetype_caption(const uint8_t type,
 
 MDBX_INTERNAL int log_error(const int err, const char *func, unsigned line);
 
-static inline int log_if_error(int err, const char *func, unsigned line) {
-  return likely(err == MDBX_SUCCESS) ? err : log_error(err, func, line);
+static inline int log_if_error(const int err, const char *func, unsigned line) {
+  if (likely(err == MDBX_SUCCESS))
+    return err;
+  int rc = log_error(err, func, line);
+#if __has_c_attribute(assume)
+  [[assume(rc == err && rc != MDBX_SUCCESS)]];
+#endif
+#if defined(__clang__) || __has_builtin(assume)
+  __builtin_assume(rc == err && rc != MDBX_SUCCESS);
+#endif
+  if (rc != err || rc == MDBX_SUCCESS) {
+#if defined(__GNUC__)
+    __builtin_unreachable();
+#elif defined(_MSC_VER) && !defined(__clang__)
+    __assume(0);
+#endif
+    rc = err;
+  }
+  return rc;
 }
 
 #define LOG_IFERR(err) log_if_error((err), __func__, __LINE__)
diff --git a/src/misc.c b/src/misc.c
index 367bcdfb..f1a58014 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -34,17 +34,21 @@ __cold int mdbx_is_readahead_reasonable(size_t volume, intptr_t redundancy) {
 int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
                       uint64_t increment) {
   int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
+  if (unlikely(rc != MDBX_SUCCESS)) {
+  bailout:
+    if (likely(result))
+      *result = ~UINT64_C(0);
     return LOG_IFERR(rc);
+  }
 
   rc = dbi_check(txn, dbi);
   if (unlikely(rc != MDBX_SUCCESS))
-    return LOG_IFERR(rc);
+    goto bailout;
 
   if (unlikely(txn->dbi_state[dbi] & DBI_STALE)) {
     rc = tbl_fetch(txn, dbi);
     if (unlikely(rc != MDBX_SUCCESS))
-      return LOG_IFERR(rc);
+      goto bailout;
   }
 
   tree_t *dbs = &txn->dbs[dbi];