BNL, Upton, Long Island, New York, USA
Proxy servers (Proxies) have been a staple of the World Wide Web infrastructure since its humble beginning. They provide a number of valuable functional services like access control, caching or logging. Historically, controls system have had little need for full fledged proxied systems as direct, unimpeded resource access is almost always preferable. This still holds true today, however unbound direct asset access can lead to performance issues, especially on older, underpowered systems. This paper describes an implementation of a fully transparent proxy server used to moderate asynchronous data flow between selected front end computers (FECs) and their clients as well as infrastructure changes required to accommodate this new platform. Finally it ventures into the future by examining additional untapped benefits of proxied control systems like write-through caching and runtime read-write modifications.
BNL, Upton, Long Island, New York, USA
For a number of years there has been an increasing desire to adopt a synoptic display suite within BNL accelerator community. Initial interest in the precursors to the modern display suites like MEDM quickly fizzled out as our users found them aesthetically unappealing and cumbersome to use. Subsequent attempts to adopt Control System Studio (CSS) also fell short when work on the abstraction bridge between CSS and our control system stalled and was eventually abandoned. Most recently, we tested the open source version of a synoptic display developed at Fermilab. It, like its previously evaluated predecessors, also seemed rough around the edges, however a few implementation details made it more appealing than every single previously mentioned solution and after a brief evaluation we settled on Synoptic as our display suite of choice. This paper describes this adoption process and goes into details on several key changes and improvements made to the original implementation – a few of which made us rethink how we want to use this tool in the future.
BNL, Upton, Long Island, New York, USA
We present a brief overview of distributed feedback systems based on the RHIC LLRF Platform. The general architecture and sub-system components of a complex feedback system are described, emphasizing the techniques and features employed to achieve deterministic and low latency data and timing delivery between local and remote sub-systems: processors, FPGA fabric components and the high level control system. In particular, we will describe how we make use of the platform to implement a widely distributed multi-processor and FPGA based longitudinal damping system, which relies on task sharing, tight synchronization and integration to achieve the desired functionality and performance.
