Files
amethyst/quartz-relay/build.gradle.kts
T
Claude d49d4a1025 perf(relay): load benchmark + bump per-session outbound buffer
Adds an opt-in load benchmark suite (`-DrunLoadBenchmark=true`)
covering: held-open WebSocket count, single + concurrent EVENT
publish throughput, and live-event fan-out latency to N
subscribers on one connection.

Numbers from a small VM (4 GiB RAM, 4 vCPU, ulimit -n 4096):

  Connections (raw WS, one REQ each)
    100   :  100 OK, 0.7 s
    500   :  500 OK, 1.2 s
    1000  : 1000 OK, 2.0 s
    2000  : 1993 OK (hits the 4096-fd ceiling: 2 fds per WS)

  Single-publisher serial publish + OK
    10000 events, 13.2 s, 760 EPS (round-trip latency bound)

  Concurrent publishers (each on its own WS)
    parallel=2  :  807 EPS
    parallel=4  : 1452 EPS
    parallel=8  : 1989 EPS  ← knee
    parallel=16 : 1704 EPS  ← SQLite single-writer ceiling
    parallel=32 : 1778 EPS

  Fanout (one publish, N active subs on a single WS)
    100 subs  : 67 ms last
    500 subs  : 52 ms last
    1000 subs : 51 ms last
    2000 subs : 111 ms last

Bumped SESSION_OUTGOING_BUFFER from 1024 → 8192. The 1024 cap was
hit by the 2000-sub fanout test (2000 outbound frames into one
session's queue), causing the relay to drop the connection as a
slow-consumer protection. 8192 fits the realistic upper bound for
a high-fan-out client (a few thousand subs on one WS) and caps
per-session memory at ~2 MiB before we drop.

Numbers also confirm:
  - The SQLite single-writer plateau is around 2000 EPS on this
    box. Production behind WAL + a faster disk should beat that.
  - Each WebSocket consumes 2 file descriptors. Operators must
    raise `ulimit -n` to ~3× their target connection count.
  - Fan-out scales sub-linearly (2000 subs ≈ 2× the latency of
    100 subs) — the bottleneck is shared (broadcast + SQLite
    write), not per-sub.

Total :quartz-relay tests: 99 (4 new benchmarks, opt-in), 0 failures.
2026-05-07 03:41:49 +00:00

71 lines
2.0 KiB
Kotlin

import org.jetbrains.kotlin.gradle.dsl.JvmTarget
plugins {
alias(libs.plugins.jetbrainsKotlinJvm)
alias(libs.plugins.serialization)
application
}
application {
mainClass.set("com.vitorpamplona.quartz.relay.MainKt")
applicationName = "quartz-relay"
}
kotlin {
jvmToolchain(21)
compilerOptions {
jvmTarget.set(JvmTarget.JVM_21)
}
}
sourceSets {
main {
kotlin.srcDir("src/main/kotlin")
}
test {
kotlin.srcDir("src/test/kotlin")
}
}
tasks.withType<Test>().configureEach {
// Forward `-DrunLoadBenchmark=true` to the test JVM so the
// perf.LoadBenchmark tests opt in. Off by default — load tests
// are noisy and slow.
systemProperty("runLoadBenchmark", System.getProperty("runLoadBenchmark") ?: "false")
// Show println output from test JVM so the benchmark numbers are
// actually visible without grepping the report XML.
testLogging {
showStandardStreams =
(System.getProperty("runLoadBenchmark") == "true")
events("standard_out")
}
}
dependencies {
api(project(":quartz"))
implementation(libs.kotlinx.coroutines.core)
implementation(libs.jackson.module.kotlin)
implementation(libs.kotlinx.serialization.json)
// Bundled SQLite driver — Relay's default in-memory EventStore creates
// an in-memory DB at runtime.
implementation(libs.androidx.sqlite.bundled.jvm)
// Ktor server engine + WebSocket plugin so Relay can serve real ws://
// traffic. CIO is the coroutine-based engine — lighter than Netty.
api(libs.ktor.server.core)
api(libs.ktor.server.cio)
api(libs.ktor.server.websockets)
// TOML parsing for the operator config file. Mirrors the section
// layout of nostr-rs-relay's config.toml so existing operators can
// port their configs nearly verbatim.
implementation(libs.fourkoma)
testImplementation(libs.kotlin.test)
testImplementation(libs.kotlinx.coroutines.test)
testImplementation(libs.secp256k1.kmp.jni.jvm)
testImplementation(libs.okhttp)
}