Move snapshot UUID generation at serialization (#7280)

UUID generation is not cheap, and therefore should be performed only when the snapshot is about to be sent. Moving UUID generation at serialization time makes it out of the critical path.
DataDog · Jul 5, 2024 · 3aea13c · 3aea13c
1 parent 23a8164
commit 3aea13c
Show file tree

Hide file tree

Showing 3 changed files with 8 additions and 1 deletion.
diff --git a/.gitlab/benchmarks.yml b/.gitlab/benchmarks.yml
@@ -8,6 +8,7 @@ variables:
   timeout: 1h
   tags: ["runner:apm-k8s-tweaked-metal"]
   image: $BASE_CI_IMAGE
+  needs: [ "build" ]
   script:
     - export ARTIFACTS_DIR="$(pwd)/reports" && mkdir -p "${ARTIFACTS_DIR}"
     - export CIRCLE_CI_TOKEN=$(aws ssm get-parameter --region us-east-1 --name ci.dd-trace-java.circleci_token --with-decryption --query "Parameter.Value" --out text)
@@ -80,6 +81,7 @@ benchmarks-post-results:
   interruptible: true
   timeout: 1h
   image: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/benchmarking-platform:java-dsm-kafka
+  needs: [ "build" ]
   script:
     - git clone --branch java/kafka-dsm-overhead https://gitlab-ci-token:${CI_JOB_TOKEN}@gitlab.ddbuild.io/DataDog/benchmarking-platform.git platform && cd platform
     - ./steps/run-benchmarks.sh
@@ -117,6 +119,7 @@ debugger-benchmarks:
   interruptible: true
   timeout: 1h
   image: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/benchmarking-platform:java-debugger
+  needs: ["build"]
   script:
     - export ARTIFACTS_DIR="$(pwd)/reports" && mkdir -p "${ARTIFACTS_DIR}"
     - git clone --branch java/debugger-benchmarks https://gitlab-ci-token:${CI_JOB_TOKEN}@gitlab.ddbuild.io/DataDog/benchmarking-platform.git /platform && cd /platform

diff --git a/dd-java-agent/agent-debugger/src/main/java/com/datadog/debugger/sink/Snapshot.java b/dd-java-agent/agent-debugger/src/main/java/com/datadog/debugger/sink/Snapshot.java
@@ -34,7 +34,6 @@ public class Snapshot {
   private String exceptionId;
 
   public Snapshot(java.lang.Thread thread, ProbeImplementation probeImplementation, int maxDepth) {
-    this.id = UUID.randomUUID().toString();
     this.version = VERSION;
     this.timestamp = System.currentTimeMillis();
     this.captures = new Captures();
@@ -105,6 +104,10 @@ public void addCaughtExceptions(List<CapturedContext.CapturedThrowable> throwabl
   }
 
   public String getId() {
+    // lazily generates snapshot id
+    if (id == null) {
+      id = UUID.randomUUID().toString();
+    }
     return id;
   }
 

diff --git a/dd-java-agent/agent-debugger/src/main/java/com/datadog/debugger/sink/SnapshotSink.java b/dd-java-agent/agent-debugger/src/main/java/com/datadog/debugger/sink/SnapshotSink.java
@@ -63,6 +63,7 @@ public boolean offer(Snapshot snapshot) {
   }
 
   String serializeSnapshot(String serviceName, Snapshot snapshot) {
+    snapshot.getId(); // Ensure id is generated
     String str = DebuggerAgent.getSnapshotSerializer().serializeSnapshot(serviceName, snapshot);
     String prunedStr = SnapshotPruner.prune(str, MAX_SNAPSHOT_SIZE, 4);
     if (prunedStr.length() != str.length()) {