**Describe the bug**

Since we upgraded to 20.10.3.30, one of our clickhouse cluster takes much more time to start. (Up to 50 minutes, and before it took ~3 minutes)
The log file is filled with
>  <Debug> DiskLocal: Reserving 1.00 MiB on disk `default`, having unreserved 16.90 TiB

Additionally, the memory consumption increases, linearly, a lot (up to arround 230 G for us) and then drop back to normal values once clickhouse finished starting up. During that loading phase, a single CPU core is used at 100%.
If that memory is not available for the machine, clickhouse gets OOMed by the kernel.


**How to reproduce**
* Issue appeared after we upgraded to ClickHouse server version 20.10.3.30

* How could I find wich of our tables may be responsible for that ?


**Expected behavior**
A fast startup :)

have_parts_with_version_metadata = true;
        }
        else
        {
            ++iter;
            continue;
        }
        
        bool version_updated = false;
        chassert(!version.creation_tid.isEmpty());
        if (!part->version.creation_csn)
        {
            auto min = TransactionLog::getCSN(version.creation_tid);
            if (!min)
            {
                
                TransactionLog::assertTIDIsNotOutdated(version.creation_tid);
                min = Tx::RolledBackCSN;
            }
            LOG_TRACE(log, "Will fix version metadata of {} after unclean restart: part has creation_tid={}, setting creation_csn={}",
                      part->name, version.creation_tid, min);
            version.creation_csn = min;
            version_updated = true;
        }
        if (!version.removal_tid.isEmpty() && !part->version.removal_csn)
        {
            auto max = TransactionLog::getCSN(version.removal_tid);
            if (max)
            {
                LOG_TRACE(log, "Will fix version metadata of {} after unclean restart: part has removal_tid={}, setting removal_csn={}",