For the intitial implementation of SSLEngine, I simply insisted that the outbound buffers be large enough to hold the max sized packet.

     * We can be smarter about estimating smaller buffer sizes later.
     * For now, force it to be large enough to handle any
     * valid SSL/TLS record.

As I said then, this can be optimized.

We may want to do in conjunction with:

    6581437: SSLEngine wastes over 32K per instance