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

140 lines
5.1 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.
*
*/
package net.sergeych.lyng
import net.sergeych.lyng.obj.Obj
import net.sergeych.lyng.obj.ObjInt
import java.io.File
import kotlin.system.measureNanoTime
import kotlin.test.Test
/**
* A/B micro-benchmark for index WRITE paths (Map[String] put, List[Int] set).
* Measures OFF vs ON for INDEX_PIC and then size 2 vs 4 (INDEX_PIC_SIZE_4).
* Produces [DEBUG_LOG] output in lynglib/build/index_write_ab_results.txt
*/
class IndexWritePathABTest {
private fun outFile(): File = File("lynglib/build/index_write_ab_results.txt")
private fun writeHeader(f: File) {
if (!f.parentFile.exists()) f.parentFile.mkdirs()
f.writeText("[DEBUG_LOG] Index WRITE PIC A/B results\n")
}
private fun appendLine(f: File, s: String) { f.appendText(s + "\n") }
private suspend fun buildMapWriteScript(keys: Int, iters: Int): Script {
// Construct map with keys k0..k{keys-1} and then perform writes in a tight loop
val initEntries = (0 until keys).joinToString(", ") { i -> "\"k$i\" => $i" }
val src = """
var acc = 0
val m = Map($initEntries)
for(i in 0..${iters - 1}) {
val k = "k" + (i % $keys)
m[k] = i
acc += (m[k] ?: 0)
}
acc
""".trimIndent()
return Compiler.compile(Source("<idx-map-write>", src), Script.defaultImportManager)
}
private suspend fun buildListWriteScript(len: Int, iters: Int): Script {
val initList = (0 until len).joinToString(", ") { i -> i.toString() }
val src = """
var acc = 0
val a = [$initList]
for(i in 0..${iters - 1}) {
val j = i % $len
a[j] = i
acc += a[j]
}
acc
""".trimIndent()
return Compiler.compile(Source("<idx-list-write>", src), Script.defaultImportManager)
}
private suspend fun runOnce(script: Script): Long {
val scope = Script.newScope()
var result: Obj? = null
val t = measureNanoTime { result = script.execute(scope) }
if (result !is ObjInt) println("[DEBUG_LOG] result=${result?.javaClass?.simpleName}")
return t
}
@Test
fun ab_index_write_paths() = runTestBlocking {
val f = outFile()
writeHeader(f)
val savedIndexPic = PerfFlags.INDEX_PIC
val savedIndexSize4 = PerfFlags.INDEX_PIC_SIZE_4
val savedCounters = PerfFlags.PIC_DEBUG_COUNTERS
try {
val iters = 250_000
val mapKeys = 256
val listLen = 1024
val mScript = buildMapWriteScript(mapKeys, iters)
val lScript = buildListWriteScript(listLen, iters)
fun header(which: String) { appendLine(f, "[DEBUG_LOG] A/B on $which (iters=$iters)") }
// Baseline OFF
PerfFlags.PIC_DEBUG_COUNTERS = true
PerfStats.resetAll()
PerfFlags.INDEX_PIC = false
PerfFlags.INDEX_PIC_SIZE_4 = false
header("Map[String] write, INDEX_PIC=OFF")
val tMOff = runOnce(mScript)
header("List[Int] write, INDEX_PIC=OFF")
val tLOff = runOnce(lScript)
appendLine(f, "[DEBUG_LOG] OFF counters: indexHit=${PerfStats.indexPicHit} indexMiss=${PerfStats.indexPicMiss}")
// PIC ON, size 2
PerfStats.resetAll()
PerfFlags.INDEX_PIC = true
PerfFlags.INDEX_PIC_SIZE_4 = false
val tMOn2 = runOnce(mScript)
val tLOn2 = runOnce(lScript)
appendLine(f, "[DEBUG_LOG] ON size=2 counters: indexHit=${PerfStats.indexPicHit} indexMiss=${PerfStats.indexPicMiss}")
// PIC ON, size 4
PerfStats.resetAll()
PerfFlags.INDEX_PIC = true
PerfFlags.INDEX_PIC_SIZE_4 = true
val tMOn4 = runOnce(mScript)
val tLOn4 = runOnce(lScript)
appendLine(f, "[DEBUG_LOG] ON size=4 counters: indexHit=${PerfStats.indexPicHit} indexMiss=${PerfStats.indexPicMiss}")
// Report
appendLine(f, "[DEBUG_LOG] Map[String] WRITE OFF=$tMOff ns, ON(2)=$tMOn2 ns, ON(4)=$tMOn4 ns")
appendLine(f, "[DEBUG_LOG] List[Int] WRITE OFF=$tLOff ns, ON(2)=$tLOn2 ns, ON(4)=$tLOn4 ns")
} finally {
PerfFlags.INDEX_PIC = savedIndexPic
PerfFlags.INDEX_PIC_SIZE_4 = savedIndexSize4
PerfFlags.PIC_DEBUG_COUNTERS = savedCounters
}
}
}
private fun runTestBlocking(block: suspend () -> Unit) {
kotlinx.coroutines.runBlocking { block() }
}