```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 (disk->getLastModified(directory_path).epochTime() >= threshold)
        return false;
    for (auto it = disk->iterateDirectory(directory_path); it->isValid(); it->next())
        if (disk->getLastModified(it->path()).epochTime() >= threshold)
            return false;
    return true;
}
size_t MergeTreeData::clearOldTemporaryDirectories(size_t custom_directories_lifetime_seconds, const NameSet & valid_prefixes)
{
    
    std::unique_lock lock(clear_old_temporary_directories_mutex, std::defer_lock);
    if (!lock.try_lock())
        return 0;
    const auto settings = getSettings();
    time_t current_time = time(nullptr);
    ssize_t deadline = current_time - custom_directories_lifetime_seconds;
    size_t cleared_count = 0;
    
    for (const auto & disk : getDisks())
    {
        if (disk->isBroken())
            continue;
        for (auto it = disk->iterateDirectory(relative_data_path); it->isValid(); it->next())
        {
            const std::string & basename = it->name();
            bool start_with_valid_prefix = false;
            for (const auto & prefix : valid_prefixes)
            {
                if (startsWith(basename, prefix))