`total_memory_tracker.setOrRaiseHardLimit(...);` in `ConfigReloader` callback (see `Server.cpp`).
{
        if (config().getBool("remap_executable", false))
        {
            LOG_DEBUG(log, "Will remap executable in memory.");
            remapExecutable();
            LOG_DEBUG(log, "The code in memory has been successfully remapped.");
        }
        if (config().getBool("mlock_executable", false))
        {
            if (hasLinuxCapability(CAP_IPC_LOCK))
            {
                try
                {
                    
                    
                    
                    auto [addr, len] = getMappedArea(reinterpret_cast<void *>(mainEntryClickHouseServer));
                    LOG_TRACE(log, "Will do mlock to prevent executable memory from being paged out. It may take a few seconds.");
                    if (0 != mlock(addr, len))
                        LOG_WARNING(log, "Failed mlock: {}", errnoToString(ErrorCodes::SYSTEM_ERROR));
                    else
                        LOG_TRACE(log, "The memory map of clickhouse executable has been mlock'ed, total {}", ReadableSize(len));
                }
                catch (...)
                {
                    LOG_WARNING(log, "Cannot mlock: {}", getCurrentExceptionMessage(false));
                }
            }
            else
            {