```sql
CREATE TABLE t
(
   id Int64, 
   d String,
   p Map(String, String)
   
)
ENGINE = ReplacingMergeTree order by id settings index_granularity  = 0;


insert into t values (1,  's', {'a':'b'});

CH starts eating RAM until it crashes

the same with

insert into t select 1,  's', map('a','b');

```

if (settings->in_memory_parts_enable_wal)
    {
        std::map<String, MutableDataPartsVector> disk_wal_part_map;
        std::mutex wal_init_lock;
        for (const auto & disk_ptr : disks)
        {
            if (disk_ptr->isBroken())
                continue;
            auto & disk_wal_parts = disk_wal_part_map[disk_ptr->getName()];
            pool.scheduleOrThrowOnError([&, disk_ptr]()
            {
                for (auto it = disk_ptr->iterateDirectory(relative_data_path); it->isValid(); it->next())
                {
                    if (!startsWith(it->name(), MergeTreeWriteAheadLog::WAL_FILE_NAME))
                        continue;
                    if (it->name() == MergeTreeWriteAheadLog::DEFAULT_WAL_FILE_NAME)
                    {
                        std::lock_guard lock(wal_init_lock);
                        if (write_ahead_log != nullptr)
                            throw Exception(
                                "There are multiple WAL files appeared in current storage policy. You need to resolve this manually",
                                ErrorCodes::CORRUPTED_DATA);
                        write_ahead_log = std::make_shared<MergeTreeWriteAheadLog>(*this, disk_ptr, it->name());
                        for (auto && part : write_ahead_log->restore(metadata_snapshot, getContext(), part_lock, is_static_storage))
                            disk_wal_parts.push_back(std::move(part));
                    }
                    else
                    {
                        MergeTreeWriteAheadLog wal(*this, disk_ptr, it->name());
                        for (auto && part : wal.restore(metadata_snapshot, getContext(), part_lock, is_static_storage))