 this limit. Notice that this limit only concerns data that has not yet reached the ERTS internal socket implementation. Defaults to 0 kB.  Senders of data to the socket are suspended if either the socket message queue is busy or the socket itself is busy.  For more information, see options low_msgq_watermark, high_watermark, and low_watermark.  Notice that distribution sockets disable the use of high_msgq_watermark and low_msgq_watermark. Instead use the distribution buffer busy limit, which is a similar feature.  {