Statistics
https://play.clickhouse.com/play?user=play#c2VsZWN0IAp0b1N0YXJ0T2ZIb3VyKGNoZWNrX3N0YXJ0X3RpbWUpIGFzIGQsCmNvdW50KCksICBncm91cFVuaXFBcnJheShwdWxsX3JlcXVlc3RfbnVtYmVyKSwgIGFueShyZXBvcnRfdXJsKQpmcm9tIGNoZWNrcyB3aGVyZSAnMjAyMi0wNi0wMScgPD0gY2hlY2tfc3RhcnRfdGltZSBhbmQgdGVzdF9uYW1lIGxpa2UgJyUwMjQ5MV9wYXJ0X2xvZ19oYXNfdGFibGVfdXVpZCUnIGFuZCB0ZXN0X3N0YXR1cyBpbiAoJ0ZBSUwnLCAnRkxBS1knKSBncm91cCBieSBkIG9yZGVyIGJ5IGQgZGVzYw==

Some times there are not output from requests.
{
    DataPartPtr part_to_delete;
    {
        auto lock = lockParts();
        auto part_name_with_state = part->getNameWithState();
        LOG_TRACE(log, "Trying to immediately remove part {}", part_name_with_state);
        if (part->getState() != DataPartState::Temporary)
        {
            auto it = data_parts_by_info.find(part->info);
            if (it == data_parts_by_info.end() || (*it).get() != part.get())
                throw Exception("Part " + part->name + " doesn't exist", ErrorCodes::LOGICAL_ERROR);
            part.reset();
            if (!((*it)->getState() == DataPartState::Outdated && it->unique()))
            {
                if ((*it)->getState() != DataPartState::Outdated)
                    LOG_WARNING(log, "Cannot immediately remove part {} because it's not in Outdated state "
                             "usage counter {}", part_name_with_state, it->use_count());
                if (!it->unique())
                    LOG_WARNING(log, "Cannot immediately remove part {} because someone using it right now "
                             "usage counter {}", part_name_with_state, it->use_count());
                return;