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.
{
    LOCK(cs_desc_man);
    unsigned int target_size;
    if (size > 0) {
        target_size = size;
    } else {
        target_size = std::max(gArgs.GetArg("-keypool", DEFAULT_KEYPOOL_SIZE), (int64_t) 1);
    }
    
    int32_t new_range_end = std::max(m_wallet_descriptor.next_index + (int32_t)target_size, m_wallet_descriptor.range_end);
    
    if (!m_wallet_descriptor.descriptor->IsRange()) {
        new_range_end = 1;
        m_wallet_descriptor.range_end = 1;
        m_wallet_descriptor.range_start = 0;
    }
    FlatSigningProvider provider;
    provider.keys = GetKeys();
    WalletBatch batch(m_storage.GetDatabase());
    uint256 id = GetID();