09:42:45.371  [blocking-thread--p3-t2] ::: TRACE o.i.persistence.mdbx.MdbxDbStore - Closing cursor Cursor[Id:1570174338, db:Database [id=21, name=datasegmentdb_19], txn:Transaction [ThreadId=259, Id=836]
09:42:45.371  [blocking-thread--p3-t2] ::: TRACE o.i.persistence.mdbx.MdbxDbStore - Closing transaction Transaction [ThreadId=259, Id=836]
09:42:45.389  [non-blocking-thread--p2-t12] ::: TRACE o.i.persistence.mdbx.MdbxDbStore - Closing cursor Cursor[Id:1324656279, db:Database [id=22, name=datasegmentdb_20], txn:Transaction [ThreadId=259, Id=836]

MDBX_Txn::MDBX_Txn(const Napi::CallbackInfo &info) : Napi::ObjectWrap<MDBX_Txn>(info) {
  unsigned int envFlags;
  unsigned int txnFlags = MDBX_TXN_READWRITE;
  int rc;
  MDBX_txn *parentTxn = nullptr;

  MDBX_env *env = info[0].As<Napi::External<MDBX_env>>().Data();
  // MDBX_Txn parentTxn = info[1].As<Napi::External<MDBX_Txn>>().Data();

  rc = mdbx_env_get_flags(env, &envFlags);
  if (rc) {
    Utils::throwMdbxError(info.Env(), rc);
    return;
  }

  if (envFlags & MDBX_RDONLY) {
    txnFlags = MDBX_TXN_RDONLY;
  }

  if (info[1].IsObject()) {
    Napi::Object options = info[1].ToObject();

    Utils::setFromObject(&txnFlags, MDBX_TXN_RDONLY, options, "readOnly");
    Utils::setFromObject(&txnFlags, MDBX_TXN_RDONLY_PREPARE, options, "prepare");
    Utils::setFromObject(&txnFlags, MDBX_TXN_TRY, options, "try");
    Utils::setFromObject(&txnFlags, MDBX_TXN_NOMETASYNC, options, "noMetaSync");
    Utils::setFromObject(&txnFlags, MDBX_TXN_NOSYNC, options, "noSync");

    Napi::Value parentTxnValue = options.Get("parentTxn");
    if (parentTxnValue.IsObject()) {
      Napi::Object parentTxnObj = parentTxnValue.ToObject();

      if (parentTxnObj.InstanceOf(MDBX_Txn::constructor.Value())) {
        // MDBX_Txn *parentTxnClass = parentTxnValue.As<Napi::External<MDBX_Txn>>().Data();
        MDBX_Txn *parentTxnClass = Napi::ObjectWrap<MDBX_Txn>::Unwrap(parentTxnObj);

        parentTxn = parentTxnClass->txn;
      } else {
        Napi::TypeError::New(info.Env(), "Invalid parentTxn: not an instance of Txn").ThrowAsJavaScriptException();

        return;
      }
    }
  }

  rc = mdbx_txn_begin(env, parentTxn, static_cast<MDBX_txn_flags>(txnFlags), &this->txn);
  if (rc) {
    Utils::throwMdbxError(info.Env(), rc);
    return;
  }
}

const txn1 = env.getTxn();
const txn2 = env.getTxn({
    parentTxn: txn1
});

console.log(txn2.info())
txn1.abort();

node: mdbx:16851: dpl_alloc: Assertion `(txn->flags & MDBX_TXN_RDONLY) == 0' failed.
Segmentation fault

root@srv1:/home/admin/keller-node-mdbx/libmdbx# ./mdbx_chk -vv /newhdd/mdbx/0-main/
mdbx_chk v0.13.2-4-gccdb6255 (2024-12-13T08:26:55+03:00, T-d5724ae9078d590b13d807bd628aae9f762d6e13)
Running for /newhdd/mdbx/0-main/ in 'read-only' mode with verbosity level 2 (of 0..9)...
   open-MADV_DONTNEED 290802734..536870912
   readahead OFF 0..290802734
 - Taking lock... done
   dxb-id bfc32c6395f7b13d-2c98e0cf3b384021
   current boot-id is unavailable
 - Peek the meta-pages...
      pagesize 4096 (4096 system), max keysize 1980..2022, max readers 114
      mapsize 2199023255552 (2.00 TiB)
      fixed datafile: 2199023255552 (2.00 TiB), 536870912 pages
    = transactions: recent 2434, latter reader 2434, lag 0
 - Traversal B-Trees by txn#2434...^C
 - Processing @GC by txn#2434...
    ! used pages mismatch (40792(walked) != 290802734(allocated - GC))
    ! GC pages mismatch (290761942(expected) != 0(GC))
 - Page allocation:
      backed by file: 536870912 pages (100.0%), 0 left to boundary (0.0%)
      used: 40792 page(s), 0.0% of backed, 0.0% of boundary
      remained: 246068178 page(s) (45.8%) of backed, 246068178 to boundary (45.8% of boundary)
      reclaimable: 0 (0.0% of backed, 0.0% of boundary), GC 0 (0.0% of backed, 0.0% of boundary)
      detained by reader(s): 0 (0.0% of backed, 0.0% of boundary), 1 reader(s), lag 0
      allocated: 290802734 page(s), 54.2% of backed, 54.2% of boundary
      available: 246068178 page(s) (45.8%) of backed, 246068178 to boundary (45.8% of boundary)
    = total 536870912 pages, backed 536870912 (100.0%), allocated 290802734 (54.2%), available 246068178 (45.8%)
 - Processing @MAIN... summary: 0 records, 0 tables, 0 key's bytes, 0 data's bytes, 0 problem(s)
   No table(s)

#define osal_malloc malloc
#define osal_calloc calloc
#define osal_realloc realloc
#define osal_free free

I've found the .so and .dll libraries for LMDB in decent versions on the internet. I haven't found this library for libmdbx. There is an old version found in an .Net binding, but it seems to be obsolete.

Should you compile the latest version of lmdx for each platform, or at least Windows and Linux, and add it to a repository somewhere ?

Do you use it in production ?

Which platforms have you deeply tested ?

Да, k6 в основном предназначен для нагрузочного тестирования веб-приложений и API, то есть для сетевых тестов. Он оптимизирован для симуляции большого количества HTTP-запросов к веб-серверам и оценки их производительности под нагрузкой. K6 позволяет анализировать такие аспекты, как время отклика, пропускная способность и стабильность системы при определенном объеме трафика.

#include "src/mitata.hpp"

int fibonacci(int n) {
  if (n <= 1) return n;
  return fibonacci(n - 1) + fibonacci(n - 2);
}

int main() {
  mitata::runner runner;
  runner.bench("noop", []() { });

  runner.summary([&]() {
    runner.bench("empty fn", []() { });
    runner.bench("fibonacci", []() { fibonacci(20); });
  });

  auto stats = runner.run();
}

LIBMDBX_API int mdbx_env_pgwalk(MDBX_txn *txn, MDBX_pgvisitor_func *visitor,
                                void *ctx, bool dont_check_keys_ordering);

      size_t reasonable_dpl_limit = (size_t)(total_ram_pages + avail_ram_pages) / 42;