lyng/lynglib/src/jvmTest/kotlin/ConcurrencyCallBenchmarkTest.kt

84 lines
2.8 KiB
Kotlin

/*
* Copyright 2025 Sergey S. Chernov real.sergeych@gmail.com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
/*
* Multithreaded benchmark to quantify SCOPE_POOL speedup on JVM.
*/
import kotlinx.coroutines.*
import net.sergeych.lyng.PerfFlags
import net.sergeych.lyng.Scope
import net.sergeych.lyng.obj.ObjInt
import kotlin.math.max
import kotlin.math.min
import kotlin.test.Test
import kotlin.test.assertEquals
class ConcurrencyCallBenchmarkTest {
private suspend fun parallelEval(workers: Int, script: String): List<Long> = coroutineScope {
(0 until workers).map { async { (Scope().eval(script) as ObjInt).value } }.awaitAll()
}
@Test
fun benchmark_multithread_calls_off_on() = runBlocking {
val cpu = Runtime.getRuntime().availableProcessors()
val workers = min(max(2, cpu), 8)
val iterations = 15_000 // per worker; keep CI fast
val script = """
fun f0() { 1 }
fun f1(a) { a }
fun f2(a,b) { a + b }
fun f3(a,b,c) { a + b + c }
fun f4(a,b,c,d) { a + b + c + d }
var s = 0
var i = 0
while (i < $iterations) {
s = s + f0()
s = s + f1(1)
s = s + f2(1, 1)
s = s + f3(1, 1, 1)
s = s + f4(1, 1, 1, 1)
i = i + 1
}
s
""".trimIndent()
val expected = (1 + 1 + 2 + 3 + 4).toLong() * iterations
// OFF
PerfFlags.SCOPE_POOL = false
val t0 = System.nanoTime()
val off = withContext(Dispatchers.Default) { parallelEval(workers, script) }
val t1 = System.nanoTime()
// ON
PerfFlags.SCOPE_POOL = true
val t2 = System.nanoTime()
val on = withContext(Dispatchers.Default) { parallelEval(workers, script) }
val t3 = System.nanoTime()
// reset
PerfFlags.SCOPE_POOL = false
off.forEach { assertEquals(expected, it) }
on.forEach { assertEquals(expected, it) }
val offMs = (t1 - t0) / 1_000_000.0
val onMs = (t3 - t2) / 1_000_000.0
val speedup = offMs / onMs
println("[DEBUG_LOG] [BENCH] ConcurrencyCallBenchmark workers=$workers iters=$iterations each: OFF=${"%.3f".format(offMs)} ms, ON=${"%.3f".format(onMs)} ms, speedup=${"%.2f".format(speedup)}x")
}
}