In the log I see things like:

    2017-09-13 03:54:33 init message: Rescanning...
    2017-09-13 03:54:33 Rescanning last 68616 blocks (from block 416339)...
    2017-09-13 03:54:40 AddToWallet xxxxx  update
    2017-09-13 03:55:33 Still rescanning. At block 418849. Progress=0.549138

I would be interested to see the wallet file name on each of these log lines.

Would there be any interest in merging such a PR?
bool ret;
                ret = reservekey.GetReservedKey(vchPubKey, true);
                if (!ret)
                {
                    strFailReason = _("Keypool ran out, please call keypoolrefill first");
                    return false;
                }
                const OutputType change_type = TransactionChangeType(coin_control.m_change_type ? *coin_control.m_change_type : m_default_change_type, vecSend);
                LearnRelatedScripts(vchPubKey, change_type);
                scriptChange = GetScriptForDestination(GetDestinationForKey(vchPubKey, change_type));
            }
            CTxOut change_prototype_txout(0, scriptChange);
            coin_selection_params.change_output_size = GetSerializeSize(change_prototype_txout, SER_DISK, 0);
            CFeeRate discard_rate = GetDiscardRate(*this, ::feeEstimator);
            
            CFeeRate nFeeRateNeeded = GetMinimumFeeRate(*this, coin_control, ::mempool, ::feeEstimator, &feeCalc);
            nFeeRet = 0;
            bool pick_new_inputs = true;
            CAmount nValueIn = 0;
            
            
            coin_selection_params.use_bnb = nSubtractFeeFromAmount == 0; 
            
            while (true)
            {
                nChangePosInOut = nChangePosRequest;
                txNew.vin.clear();
                txNew.vout.clear();
                bool fFirst = true;
                CAmount nValueToSelect = nValue;