OSMs: SimulationControl with 'Do HVAC Sizing Simulation for Sizing Periods' Causes Timeout

[corymosiman12]

Jeez louise. I think I figured out what the problem was, but wanted to document here. Also, wanted to get your opinion @kbenne @anyaelena if this is something Alfalfa should be resilient to or not (as my solution kinda just bypasses the issue):

Setup

Using images:

• nrel/alfalfa-grafana: a4b4ed455d17
• nrel/alfalfa-web: b7ff5548918b
• nrel/alfalfa-worker: 3fda3e1c3789

I was going through the following:

• Generate OSM using 'Create Typical' measure
• Use that OSM to submit to alfalfa (no modifications)

Issue

alfalfa_worker was throwing a socket timeout error:

alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Server started on 127.0.0.1:43679
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Wrote socket.cfg
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Launch EnergyPlus
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Traceback (most recent call last):
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |   File "step_sim/step_osm.py", line 31, in <module>
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |     m.run()
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |   File "/alfalfa/alfalfa_worker/step_sim/model_advancer.py", line 82, in run
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |     self.init_sim()
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |   File "/alfalfa/alfalfa_worker/step_sim/osm_model_advancer.py", line 89, in init_sim
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |     [self.ep.status, self.ep.msg] = self.ep.accept_socket()
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |   File "/usr/local/lib/python3.6/dist-packages/mlep/mlep_process.py", line 162, in accept_socket
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |     (self.comm_socket, self.client_address) = self.server_socket.accept()
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |   File "/usr/lib/python3.6/socket.py", line 205, in accept
alfalfa_worker.1.yknoro81sx1l@docker-desktop    |     fd, addr = self._accept()
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | socket.timeout: timed out
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | 2021-04-08 15:22:30,829 - alfalfa_worker - INFO - step_sim unsuccessful for: 178649b0-987e-11eb-b77d-c35343e29841
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | INFO:alfalfa_worker:step_sim unsuccessful for: 178649b0-987e-11eb-b77d-c35343e29841
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | 2021-04-08 15:22:31,256 - alfalfa_worker - INFO - step_sim return code: 1
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | INFO:alfalfa_worker:step_sim return code: 1
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Error when connecting to socket: Connection refused
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Program terminated: EnergyPlus Terminated--Error(s) Detected.
alfalfa_worker.1.yknoro81sx1l@docker-desktop    | Error when connecting to socket: Connection refused

When I got down into it, I found the following:

utilSocket.log:

utilSocket: Establishing socket based on file socket.cfg.
Getting socket port number.
Received socket port number 40903.
Socket port number = 40903.
Socket opened, sockfd = 16.
Error when connecting to socket: Connection refused
utilSocket: Establishing socket based on file socket.cfg.
Getting socket port number.
Received socket port number 40903.
Socket port number = 40903.
Socket opened, sockfd = 4.
Error when connecting to socket: Connection refused

mlep.log

Beginning Primary Simulation
Initializing New Environment Parameters
Warming up {1}
Instantiating Building Controls Virtual Test Bed
ExternalInterface initializes.
**FATAL:Error in ExternalInterface: Check EnergyPlus *.err file.
EnergyPlus Run Time=00hr 00min 32.99sec


EnergyPlus output files are located in: "/simulate/72137b10-985a-11eb-b91d-1df214baffa9/simulation/Output"




===== EnergyPlus terminated with error =====

Output/sim.err:

   ************* Beginning Simulation
   ** Severe  ** ExternalInterface: Could not open socket. File descriptor = -1.
   **  Fatal  ** Error in ExternalInterface: Check EnergyPlus *.err file.
   ...Summary of Errors that led to program termination:
   ..... Reference severe error count=1
   ..... Last severe error=ExternalInterface: Could not open socket. File descriptor = -1.
. . . 
   ************* ===== Final Error Summary =====
   ************* The following error categories occurred.  Consider correcting or noting.
   ************* Nominally Unused Constructions
   ************* ..The nominally unused constructions warning is provided to alert you to potential conditions that can cause
   ************* ..extra time during simulation. Each construction is calculated by the algorithm indicated in the HeatBalanceAlgorithm
   ************* ..object. You may remove the constructions indicated (when you use the DisplayExtraWarnings option).
   *************
   ************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 1 Severe Errors.
   ************* EnergyPlus Sizing Error Summary. During Sizing: 31 Warning; 0 Severe Errors.
   ************* EnergyPlus Terminated--Fatal Error Detected. 51565 Warning; 1 Severe Errors; Elapsed Time=00hr 00min 32.99sec

Solution / Workaround

• The issue has to do with the OS:SimulationControl, specifically, the Do HVAC Sizing Simulation for Sizing Periods

Doesn't work:

OS:SimulationControl,
  {fe5b5f3c-f637-4fd1-a2b3-f4d09456dccb}, !- Handle
  Yes,                                    !- Do Zone Sizing Calculation
  Yes,                                    !- Do System Sizing Calculation
  Yes,                                    !- Do Plant Sizing Calculation
  No,                                     !- Run Simulation for Sizing Periods
  Yes,                                    !- Run Simulation for Weather File Run Periods
  0.04,                                   !- Loads Convergence Tolerance Value {W}
  0.2,                                    !- Temperature Convergence Tolerance Value {deltaC}
  FullInteriorAndExterior,                !- Solar Distribution
  25,                                     !- Maximum Number of Warmup Days
  6,                                      !- Minimum Number of Warmup Days
  Yes,                                    !- Do HVAC Sizing Simulation for Sizing Periods
  1;                                      !- Maximum Number of HVAC Sizing Simulation Passes

• Changing the parameter to No or deleting the last two lines solves the issue.

Recommend Next Steps:

• Decide if this is a feature we want to support (seems low ROI...)
• If not, we should probably:
  • Change this parameter to 'No' if defined OR remove the two fields