`total_memory_tracker.setOrRaiseHardLimit(...);` in `ConfigReloader` callback (see `Server.cpp`).
{
    Poco::Logger * log = &logger();
    UseSSL use_ssl;
    MainThreadStatus::getInstance();
    registerFunctions();
    registerAggregateFunctions();
    registerTableFunctions();
    registerStorages();
    registerDictionaries();
    registerDisks();
    registerFormats();
    CurrentMetrics::set(CurrentMetrics::Revision, ClickHouseRevision::getVersionRevision());
    CurrentMetrics::set(CurrentMetrics::VersionInteger, ClickHouseRevision::getVersionInteger());
    if (ThreadFuzzer::instance().isEffective())
        LOG_WARNING(log, "ThreadFuzzer is enabled. Application will run slowly and unstable.");
#if !defined(NDEBUG) || !defined(__OPTIMIZE__)
    LOG_WARNING(log, "Server was built in debug mode. It will work slowly.");
#endif
#if defined(SANITIZER)
    LOG_WARNING(log, "Server was built with sanitizer. It will work slowly.");
#endif
    /** Context contains all that query execution is dependent:
      *  settings, available functions, data types, aggregate functions, databases, ...
      */
    auto shared_context = Context::createShared();
    auto global_context = std::make_unique<Context>(Context::createGlobal(shared_context.get()));
    global_context_ptr = global_context.get();