web/backend: Show elapsed time

web/backend/Dockerfile

@@ -6,7 +6,7 @@ WORKDIR /app
 COPY Project.toml /app/Backend/
 COPY src /app/Backend/src
 RUN julia --project=. -e 'using Pkg; Pkg.develop(path="Backend"); Pkg.add("HiGHS"); Pkg.add("JuMP"); Pkg.precompile()'
-COPY docker/startup.jl ./
+COPY startup.jl ./
 
 # Set timezone to Chicago
 ENV TZ=America/Chicago
@@ -17,4 +17,4 @@ ENV UCJL_HOST="0.0.0.0"
 ENV UCJL_PORT="9000"
 
 # Run the server
-CMD ["julia", "--threads", "1", "--procs", "1", "--project=.", "startup.jl"]
+CMD ["julia", "--threads", "1", "--procs", "4", "--project=.", "startup.jl"]

web/backend/Makefile

@@ -13,3 +13,11 @@ docker-run:
 		--memory 16g \
 		--cpus 4 \
 		ucjl-backend
+
+test:
+	clear; julia --threads 1 --procs 1 --project=test -e "using BackendT; runtests()"
+
+run:
+	julia --procs 1 --project=. startup.jl
+
+.PHONY: test

web/backend/Project.toml

@@ -8,7 +8,9 @@ CodecZlib = "944b1d66-785c-5afd-91f1-9de20f533193"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
 Distributed = "8ba89e20-285c-5b6f-9357-94700520ee1b"
 HTTP = "cd3eb016-35fb-5094-929b-558a96fad6f3"
+HiGHS = "87dc4568-4c63-4d18-b0c0-bb2238e4078b"
 JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
+JuMP = "4076af6c-e467-56ae-b986-b466b2749572"
 Logging = "56ddb016-857b-54e1-b83d-db4d58db5568"
 Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
@@ -19,7 +21,9 @@ CodecZlib = "0.7.8"
 Dates = "1.11.0"
 Distributed = "1.11.0"
 HTTP = "1.10.19"
+HiGHS = "1.20.1"
 JSON = "0.21.4"
+JuMP = "1.29.2"
 Logging = "1.11.0"
 Printf = "1.11.0"
 Random = "1.11.0"

web/backend/src/jobs.jl

@@ -8,73 +8,115 @@ import Base: put!
 Base.@kwdef mutable struct JobProcessor
     pending = RemoteChannel(() -> Channel{String}(Inf))
     processing = RemoteChannel(() -> Channel{String}(Inf))
+    completed = RemoteChannel(() -> Channel{String}(Inf))
     shutdown = RemoteChannel(() -> Channel{Bool}(1))
-    worker_pid = nothing
+    worker_pids = []
-    monitor_task = nothing
+    worker_tasks = []
     work_fn = nothing
+    master_task = nothing
+    job_status = Dict()
+    job_position = Dict()
+    pending_queue = []
+end
+
+function update_positions!(processor::JobProcessor)
+    for (i, job_id) in enumerate(processor.pending_queue)
+        processor.job_position[job_id] = i
+    end
 end
 
 function Base.put!(processor::JobProcessor, job_id::String)
-    return put!(processor.pending, job_id)
+    put!(processor.pending, job_id)
+    processor.job_status[job_id] = "pending"
+    push!(processor.pending_queue, job_id)
+    update_positions!(processor)
 end
 
-function isbusy(processor::JobProcessor)
+function master_loop(processor)
-    return isready(processor.pending) || isready(processor.processing)
+    @info "Starting master loop"
+    while true
+        # Check for shutdown signal
+        if isready(processor.shutdown)
+            break
         end
 
-function worker_loop(pending, processing, shutdown, work_fn)
+        # Check for processing jobs
+        while isready(processor.processing)
+            job_id = take!(processor.processing)
+            processor.job_status[job_id] = "processing"
+            filter!(x -> x != job_id, processor.pending_queue)
+            delete!(processor.job_position, job_id)
+            update_positions!(processor)
+        end
+
+        # Check for completed jobs
+        while isready(processor.completed)
+            job_id = take!(processor.completed)
+            delete!(processor.job_status, job_id)
+            delete!(processor.job_position, job_id)
+        end
+
+        sleep(0.1)
+    end
+end
+
+function worker_loop(pending, processing, completed, shutdown, work_fn)
     @info "Starting worker loop"
     while true
         # Check for shutdown signal
         if isready(shutdown)
-            @info "Shutdown signal received"
             break
         end
 
-        # Wait for a job with timeout
+        # Check for pending tasks
-        if !isready(pending)
+        if isready(pending)
-            sleep(0.1)
-            continue
-        end
-
-        # Move job from pending to processing queue
             job_id = take!(pending)
             put!(processing, job_id)
             @info "Job started: $job_id"
-
-        # Run work function
             try
-            work_fn(job_id)
+                work_time = @elapsed work_fn(job_id)
+                @info "Job finished: $job_id ($work_time s)"
+                put!(completed, job_id)
             catch e
                 @error "Job failed: job $job_id"
             end
+        end
 
-        # Remove job from processing queue
+        sleep(0.1)
-        take!(processing)
-        @info "Job finished: $job_id"
     end
 end
 
 function start(processor::JobProcessor)
-    processor.monitor_task = @spawn begin
+    # Get list of available worker processes
+    worker_pids = workers()
+    @info "Starting job processor with $(length(worker_pids)) worker(s)"
+
+    # Start a worker loop on each worker process
+    for pid in worker_pids
+        task = @spawnat pid begin
             worker_loop(
                 processor.pending,
                 processor.processing,
+                processor.completed,
                 processor.shutdown,
                 processor.work_fn,
             )
         end
+        push!(processor.worker_pids, pid)
+        push!(processor.worker_tasks, task)
+    end
+
+    # Start master loop (after spawning workers to avoid serialization issues)
+    processor.master_task = @async master_loop(processor)
+
     return
 end
 
 function stop(processor::JobProcessor)
     put!(processor.shutdown, true)
-    if processor.monitor_task !== nothing
+    wait(processor.master_task)
-        try
+    for (i, task) in enumerate(processor.worker_tasks)
-            wait(processor.monitor_task)
+        wait(task)
-        catch e
-            @warn "Error waiting for worker task" exception=e
-        end
     end
     return
 end

web/backend/src/log.jl

@@ -31,6 +31,8 @@ end
 
 function setup_logger()
     global_logger(TimeLogger())
-    @spawn global_logger(TimeLogger())
+    for pid in workers()
+        @spawnat pid global_logger(TimeLogger())
+    end
     return
 end

web/backend/src/server.jl

@@ -53,7 +53,7 @@ function submit(req, processor::JobProcessor)
     return HTTP.Response(200, RESPONSE_HEADERS, response_body)
 end
 
-function jobs_view(req)
+function jobs_view(req, processor)
     # Extract job_id from URL path /api/jobs/{job_id}/view
     path_parts = split(req.target, '/')
     job_id = path_parts[4]
@@ -74,9 +74,19 @@ function jobs_view(req)
     output_path = joinpath(job_dir, "output.json")
     output_content = isfile(output_path) ? read(output_path, String) : nothing
 
-    # Create response JSON
+    # Read job status
-    response_data = Dict("log" => log_content, "solution" => output_content)
+    job_status = "unknown"
+    if output_content !== nothing
+        job_status = "completed"
+    elseif haskey(processor.job_status, job_id)
+        job_status = processor.job_status[job_id]
+    end
 
+    # Read job position (0 if already processed or not found)
+    job_position = get(processor.job_position, job_id, 0)
+
+    # Create response JSON
+    response_data = Dict("log" => log_content, "solution" => output_content, "status" => job_status, "position" => job_position)
     response_body = JSON.json(response_data)
     return HTTP.Response(200, RESPONSE_HEADERS, response_body)
 end
@@ -134,7 +144,7 @@ function start_server(host, port; optimizer)
     HTTP.register!(router, "POST", "/api/submit", req -> submit(req, processor))
 
     # Register job/*/view endpoint
-    HTTP.register!(router, "GET", "/api/jobs/*/view", jobs_view)
+    HTTP.register!(router, "GET", "/api/jobs/*/view", req -> jobs_view(req, processor))
 
     server = HTTP.serve!(router, host, port; verbose = false)
     return ServerHandle(server, processor)

web/backend/startup.jl

@@ -1,10 +1,7 @@
-#!/usr/bin/env julia
-
 # UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
 # Copyright (C) 2025, UChicago Argonne, LLC. All rights reserved.
 # Released under the modified BSD license. See COPYING.md for more details.
 
-# Load required packages
 using HiGHS
 using JuMP
 using Backend
@@ -15,10 +12,16 @@ const UCJL_PORT = parse(Int, get(ENV, "PORT", "9000"))
 println("Starting UnitCommitment Backend Server...")
 println("Host: $UCJL_HOST")
 println("Port: $UCJL_PORT")
-println("Press Ctrl+C to stop the server")
 
 Backend.setup_logger()
-server = Backend.start_server(UCJL_HOST, UCJL_PORT; optimizer = optimizer_with_attributes(HiGHS.Optimizer, "mip_rel_gap" => 0.001))
+server = Backend.start_server(
+    UCJL_HOST,
+    UCJL_PORT;
+    optimizer = optimizer_with_attributes(
+        HiGHS.Optimizer, "mip_rel_gap" => 0.001,
+        "threads" => 1,
+    )
+)
 try
     wait()
 catch e

web/backend/test/src/server_test.jl

@@ -26,10 +26,7 @@ function server_test_usage()
         @test length(job_id) == 16
 
         # Wait for jobs to finish
-        sleep(5)
+        sleep(10)
-        while isbusy(server.processor)
-            sleep(0.1)
-        end
 
         # Verify the compressed file was saved correctly
         job_dir = joinpath(Backend.basedir, "jobs", job_id)
@@ -52,6 +49,7 @@ function server_test_usage()
         @test haskey(view_data, "solution")
         @test view_data["log"] !== nothing
         @test view_data["solution"] !== nothing
+        @test view_data["status"] == "completed"
 
         # Clean up
         rm(job_dir, recursive = true)

web/frontend/src/components/Jobs/Jobs.tsx

@@ -15,6 +15,7 @@ import formStyles from "../Common/Forms/Form.module.css";
 interface JobData {
   log: string;
   solution: any;
+  position: number;
 }
 
 const Jobs = () => {
@@ -81,7 +82,9 @@ const Jobs = () => {
         <SectionHeader title="Optimization log"></SectionHeader>
         <div className={formStyles.FormWrapper}>
           <div className={styles.SolverLog} ref={logRef}>
-            {jobData ? jobData.log : "Loading..."}
+            {jobData
+              ? jobData.log || `Waiting for ${jobData.position} other optimization job(s) to finish...`
+              : "Loading..."}
           </div>
         </div>
       </div>