HotRod client write buffer is too large --------------------------------------- Key: ISPN-5740 URL: https://issues.jboss.org/browse/ISPN-5740 Project: Infinispan Issue Type: Bug Components: Server Affects Versions: 8.0.0.Final Reporter: Dan Berindei Assignee: Dan Berindei Fix For: 8.1.0.Alpha1, 8.1.0.Final, 8.0.2.Final The ISPN-1015 fix added a buffer to the HotRod client transport to reduce the number of syscalls. But that buffer's size is not fixed, instead it's based on {{Socket.getSendBufferSize()}}, which in turn is based on the kernel's {{net.core.wmem_max}}. JGroups needs {{net.core.wmem_max}} greater or equal than {{UDP.ucast_send_buf_size}}, which is 1MB by default. That is probably too much for the {{TcpTransport}}'s buffer, because the buffer is also duplicated in the OS.