[jboss-jira] [JBoss JIRA] (JGRP-1826) Discovery: file-based discovery protocols should not send discovery requests

Discovery: file-based discovery protocols should not send discovery requests ---------------------------------------------------------------------------- Key: JGRP-1826 URL: https://issues.jboss.org/browse/JGRP-1826 Project: JGroups Issue Type: Enhancement Reporter: Bela Ban Assignee: Bela Ban Fix For: 3.5 When a node stores its information in a directory ({{FILE_PING}}, {{S3_PING}} or {{GOOGLE_PING}}), then we can optimize discovery by implementing a few things: * After reading all files, we send each node (represented by a file) a discovery request. That node processes the request and sends back a discovery response. This is unneeded traffic, especially with large clusters. Instead ** Read all files and add the information read from the files into the local caches (logical_addr_cache, UUID cache etc). This is the same as processing discovery responses from all members * Determine the coordinators directly from the file information. Perhaps we could even create a special file which contains information about the coordinator. ** This would prevent partitions from happening when starting up a large number of nodes: as long as that special file exists, nobody else will take ownership of it. When the coord leaves or crashes, we atomically replace the special file