Default to zstd compression for profile uploads on Node.js 24+

Author: szegedi

integration-tests/profiler/profiler.spec.js

@@ -24,6 +24,7 @@ if (process.platform !== 'win32') {
 }
 
 const TIMEOUT = 30000
+const isAtLeast24 = satisfies(process.versions.node, '>=24.0.0')
 
 function checkProfiles (agent, proc, timeout,
   expectedProfileTypes = DEFAULT_PROFILE_TYPES, expectBadExit = false, expectSeq = true
@@ -95,9 +96,9 @@ function processExitPromise (proc, timeout, expectBadExit = false) {
 }
 
 async function getLatestProfile (cwd, pattern) {
-  const pprofGzipped = await readLatestFile(cwd, pattern)
-  const pprofUnzipped = zlib.gunzipSync(pprofGzipped)
-  return { profile: Profile.decode(pprofUnzipped), encoded: pprofGzipped.toString('base64') }
+  const pprofCompressed = await readLatestFile(cwd, pattern)
+  const pprofUncompressed = zlib[isAtLeast24 ? 'zstdDecompressSync' : 'gunzipSync'](pprofCompressed)
+  return { profile: Profile.decode(pprofUncompressed), encoded: pprofCompressed.toString('base64') }
 }
 
 async function readLatestFile (cwd, pattern) {
@@ -360,7 +361,7 @@ describe('profiler', () => {
       const execArgv = []
       if (satisfies(process.versions.node, '>=22.9.0')) {
         env.DD_PROFILING_ASYNC_CONTEXT_FRAME_ENABLED = 1
-        if (!satisfies(process.versions.node, '>=24.0.0')) {
+        if (!isAtLeast24) {
           // For Node 22.9.0+, use the experimental command line flag for Node to enable
           // async context frame. Node 24 has it enabled by default.
           execArgv.push('--experimental-async-context-frame')

packages/dd-trace/src/profiling/config.js

@@ -179,6 +179,9 @@ class Config {
 
     this.heapSamplingInterval = options.heapSamplingInterval ??
       (Number(DD_PROFILING_HEAP_SAMPLING_INTERVAL) || 512 * 1024)
+
+    const isAtLeast24 = satisfies(process.versions.node, '>=24.0.0')
+
     const uploadCompression0 = options.uploadCompression ?? DD_PROFILING_DEBUG_UPLOAD_COMPRESSION ?? 'on'
     let [uploadCompression, level0] = uploadCompression0.split('-')
     if (!['on', 'off', 'gzip', 'zstd'].includes(uploadCompression)) {
@@ -206,9 +209,12 @@ class Config {
       }
     }
 
-    // Default to gzip
+    // Default to either zstd (on Node.js 24+) or gzip (earlier Node.js). We could default to ztsd
+    // everywhere as we ship a Rust zstd compressor for older Node.js versions, but on 24+ we use
+    // the built-in one that runs asynchronously on libuv worker threads, just as gzip does. This is
+    // the least disruptive choice.
     if (uploadCompression === 'on') {
-      uploadCompression = 'gzip'
+      uploadCompression = isAtLeast24 ? 'zstd' : 'gzip'
     }
 
     this.uploadCompression = { method: uploadCompression, level }
@@ -224,7 +230,7 @@ class Config {
 
     let canUseAsyncContextFrame = false
     if (samplingContextsAvailable) {
-      if (satisfies(process.versions.node, '>=24.0.0')) {
+      if (isAtLeast24) {
         canUseAsyncContextFrame = !hasExecArg('--no-async-context-frame')
       } else if (satisfies(process.versions.node, '>=22.9.0')) {
         canUseAsyncContextFrame = hasExecArg('--experimental-async-context-frame')
@@ -234,7 +240,7 @@ class Config {
     if (this.asyncContextFrameEnabled && !canUseAsyncContextFrame) {
       if (!samplingContextsAvailable) {
         turnOffAsyncContextFrame(`on ${process.platform}`)
-      } else if (satisfies(process.versions.node, '>=24.0.0')) {
+      } else if (isAtLeast24) {
         turnOffAsyncContextFrame('with --no-async-context-frame')
       } else if (satisfies(process.versions.node, '>=22.9.0')) {
         turnOffAsyncContextFrame('without --experimental-async-context-frame')

packages/dd-trace/test/profiling/config.spec.js

@@ -19,6 +19,8 @@ const { ConsoleLogger } = require('../../src/profiling/loggers/console')
 
 const samplingContextsAvailable = process.platform !== 'win32'
 const oomMonitoringSupported = process.platform !== 'win32'
+const isAtLeast24 = satisfies(process.versions.node, '>=24.0.0')
+const zstdOrGzip = isAtLeast24 ? 'zstd' : 'gzip'
 
 describe('config', () => {
   let Config
@@ -60,7 +62,7 @@ describe('config', () => {
     assert.strictEqual(config.profilers[1].codeHotspotsEnabled(), samplingContextsAvailable)
     assert.strictEqual(config.v8ProfilerBugWorkaroundEnabled, true)
     assert.strictEqual(config.cpuProfilingEnabled, samplingContextsAvailable)
-    assert.strictEqual(config.uploadCompression.method, 'gzip')
+    assert.strictEqual(config.uploadCompression.method, zstdOrGzip)
     assert.strictEqual(config.uploadCompression.level, undefined)
   })
 
@@ -510,7 +512,7 @@ describe('config', () => {
   }
 
   describe('async context', () => {
-    const isSupported = samplingContextsAvailable && satisfies(process.versions.node, '>=24.0.0')
+    const isSupported = samplingContextsAvailable && isAtLeast24
     describe('where supported', () => {
       it('should be on by default', function () {
         if (!isSupported) {
@@ -590,15 +592,15 @@ describe('config', () => {
     }
 
     it('should accept known methods', () => {
-      expectConfig(undefined, 'gzip', undefined)
+      expectConfig(undefined, zstdOrGzip, undefined)
       expectConfig('off', 'off', undefined)
-      expectConfig('on', 'gzip', undefined)
+      expectConfig('on', zstdOrGzip, undefined)
       expectConfig('gzip', 'gzip', undefined)
       expectConfig('zstd', 'zstd', undefined)
     })
 
     it('should reject unknown methods', () => {
-      expectConfig('foo', 'gzip', undefined, 'Invalid profile upload compression method "foo". Will use "on".')
+      expectConfig('foo', zstdOrGzip, undefined, 'Invalid profile upload compression method "foo". Will use "on".')
     })
 
     it('should accept supported compression levels in methods that support levels', () => {
@@ -618,7 +620,7 @@ describe('config', () => {
 
     it('should reject compression levels in methods that do not support levels', () => {
       ['on', 'off'].forEach((method) => {
-        const effectiveMethod = method === 'on' ? 'gzip' : method
+        const effectiveMethod = method === 'on' ? zstdOrGzip : method
         expectConfig(`${method}-3`, effectiveMethod, undefined,
           `Compression levels are not supported for "${method}".`)
         expectConfig(`${method}-foo`, effectiveMethod, undefined,