When running walletpassphrase on a large wallet.dat (ie about 300,000 segwit P2SH addresses) the command sometimes takes a very long time, and if command is run multiple times at once (while running slow) it causes bitcoin core to freeze (stops syncing and requires kill -9 to stop/restart)

During the locked up walletpassphrase commands being run the following messages start to appear in the debug.log:

`018-01-24 01:01:04 socket sending timeout: 1201s`

Note that this problem is intermittent, so sometimes the command runs instantly, other times it takes a few minutes, and other times it completely freezes the node.
return IsMineResult::INVALID;
        }
        CScriptID scriptID = CScriptID(uint160(vSolutions[0]));
        CScript subscript;
        if (keystore.GetCScript(scriptID, subscript)) {
            ret = std::max(ret, recurse_scripthash ? IsMineInner(keystore, subscript, IsMineSigVersion::P2SH) : IsMineResult::SPENDABLE);
        }
        break;
    }
    case TX_WITNESS_V0_SCRIPTHASH:
    {
        if (sigversion == IsMineSigVersion::WITNESS_V0) {
            
            return IsMineResult::INVALID;
        }
        if (sigversion == IsMineSigVersion::TOP && !keystore.HaveCScript(CScriptID(CScript() << OP_0 << vSolutions[0]))) {
            break;
        }
        uint160 hash;
        CRIPEMD160().Write(&vSolutions[0][0], vSolutions[0].size()).Finalize(hash.begin());
        CScriptID scriptID = CScriptID(hash);
        CScript subscript;
        if (keystore.GetCScript(scriptID, subscript)) {
            ret = std::max(ret, recurse_scripthash ? IsMineInner(keystore, subscript, IsMineSigVersion::WITNESS_V0) : IsMineResult::SPENDABLE);
        }
        break;
    }
    case TX_MULTISIG:
    {