LCE daemon and its use of threads to maintain connections to multiple pSeries eServers
Original Publication Date: 2001-Jul-23
Included in the Prior Art Database: 2003-Jun-20
LCE daemon and its use of threads to maintain connections to multiple pSeries eServers The LCED (Local Control Element Daemon) is a router process that runs on a standalone PC (aka the Platform Management Console (PMC). This PMC could attach to pSeries eServers. The LCED controls all communication from any PMC application to the CSP (Common Service Processor) in a pSeries eServer system, and vice-versa. This daemon has to be able to accommodate multiple CSPs attached via serial connection in its first release, as well as future new objects (i.e. switch units, bulk power assembly, etc.) and communications types (i.e. ethernet, TCP/IP, etc.). The LCE needs to be able to communicate to multiple PMC applications, multiplexing data packets they may send to multiple CSPs. If we have one thread trying to handle all of the communications, there could be bottlenecks. For instance, one PMC application could be engaged in communication to a particular CSP. Any other communications (whether downstream to the CSP or upstream to another PMC application) would have to wait for the first application to complete its transaction. This becomes important when considering an PMC application such as the Terminal Emulator (Virtual TTY), which needs to get data from the CSP up to the PMC user as quickly as possible.