V4 July Meeting Agenda

This is an informal agenda for the core developers design meeting.

Location and Facilities

The meeting will be held in conference room C010 of building 433, which is a Lab/Office Module (LOM) about a third of the way clockwise around the ring from the APS main building (401), between sectors 10 and 11 (MRCAT & BESSRC). There is ample parking right outside building 433; if you're driving in you probably won't want to park in the building 401 parking lots since it's a bit of a walk from there.

There will be an LCD projector and screen in the room, and wireless networking is available.

Agenda

Wednesday

10:00 Demo of commercial control system in Bldg 401 B2100

Friday

Subgroup meetings by agreement if needed; we have the room available today, but some people may be travelling home.

Discussion Topics

This is a list of topics Andrew thinks we need to talk about:

• Who is EPICS V4 being written for?
  • Minimum requirements of the OS (should we support Tornado 2.x? No => no 68K)
• epicsTypes, Data Access types, network types, mapping these to platform types.
  • How to introspect arrays without instanciating them?
  • epicsString vs stringSegment, epicsArrayBuffer etc.
• New asynchronous record processing design
  • Splits records up into smaller objects
  • How to link these objects together?
• Replacement for periodic scan threads
• Split libOSI out of libCom?
• What to do about the errlog client & server code
• Flex & Antelope => updated Flex, Bison?
  • We need these for: Access Security, probably for DB file parser, SNC
• Build system - carry on like we have been, or redesign? Options:
  1. Continue with R3.14 build system
  2. Use the modified build system on the CVS main trunk (R3.15)
  3. Adopt GNU autoconf & automake
  4. Parse configuration and Makefiles in Perl, generate specific Makefile
  5. Something else?
• Source code revision management - Subversion repository at APS

Marty provided this list:

• V4 Database
  • Database Definition File Syntax - 1 hour - Andrew Johnson
  • Record Instance syntax - 1 hour - Andrew Johnson
  • Generated Header Files and Introspection - 1 hour - Marty Kraimer
  • Interfaces for accessing records - 1 hour - Marty Kraimer
  • Record Processing - 1 hour - Marty Kraimer
• Discussion of dataAccess and epicsTypes 2 hour session

These were topics from Bob:

• Mechanism for event set - extensible? How many are needed?
• Super Record (Andrew/Bob): Present a study on the ability and issues in creating super records.
• User extensible fields (Marty, Kay and Matthias): Present a study on the ability to extend record funciontality with an extension of records.
• Middleware Interfaces to CA server (Ralph and Benjamin): Present the requirements and a preliminary design for a layer between the database posting mechanism and services that are interested in this data.

Network Communication Services:

• Name service (Doug and Kay): Present the function and a preliminary design for the name services.
• Channel Access Client user interface (Kay and Doug): Provide the user perspective of the CA Client interface.
• Channel Access Client (Jeff): Show the connection of the CA Client interface to the low level calls provided.
• Channel Access Network Protocol (Jeff): Specification of the protocol on the wire will be provided prior to implementation.
• Channel Access Services (Jeff): Show the interface from the database middle layer, and design for the filtering.
• Property Catalogs and Events (Bob): Provide a list of properties and events that will be supported.
• EPICS Gateway (Ralph and Benjamin): Present the requirements and preliminary design for the gateway to support all channel access features for filtering and events.