russell@unturf.com 9934133dcf whitepaper: 312 sites / 151 ecosystems — wave2+3 defect tables and PDF rebuild

Add 88 new defect entries to HIGH and MEDIUM tables:
  HIGH: mysql-0001/0002, mariadb-0001, redis-0001/0002, valkey-0001/0002, openvpn-0001,
        vlc-0001, prometheus-0001, otel-collector-0001, cockroachdb-0001..0004,
        tidb-0001..0008, kubernetes-0001/0002, go-0001, kotlin-0002, scala-0001,
        allegro5-0001, sdl2-0001, grafana-0001, clickhouse-0001, duckdb-0001,
        mongodb-0001, envoy-0001, istio-0001, cilium-0001, linkerd2-0001,
        linux-0001/0002/0003, tor-0002/0003, curl-0001, julia-0001, lua-0001,
        perl5-0001, nats-0001, spring-0003/0004, tomcat-0001, onos-0002, odl-0002

  MEDIUM: helm-0001, mariadb-0002, openssl-0001/0002, memcached-0001,
          cassandra-0001..0004, flink-0001, storm-0001/0002, zookeeper-0001..0003,
          pip-0001, gradle-0001, nginx-0001, haproxy-0001, caddy-0001, varnish-0001,
          ffmpeg-0001, gstreamer-0001, raylib-0001, love2d-0001, php-0001/0002,
          r-source-0001, cpython-0002, ruby-0001, rabbitmq-0003/0004, activemq-0001,
          ovs-0001, onos-0003, odl-0002, jetty-0001

PDF: 976K

2026-03-27 15:23:43 -04:00

1.7 KiB

Raw Blame History

odl-0002: ShardManager ShardManagerSnapshot.getShardList().contains() — O(n) ImmutableList membership

Status

PATCHED

Target

opendaylight/controller

File

opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/persisted/ShardManagerSnapshot.java opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/shardmanager/ShardManager.java

Symptom

On every CreateShard event, ShardManager.doCreateShard() calls currentSnapshot.getShardList().contains(shardName) to check whether the shard was present in the recovered snapshot. getShardList() returns an ImmutableList<String>. With S shards in the snapshot, this is O(S) per shard creation. During cluster recovery with hundreds of shards, every shard recreation pays O(S) to check membership in the snapshot — O(S²) total across all creations.

Root cause

// ShardManagerSnapshot.java:31
public List<String> getShardList() {
    return shardList;  // ImmutableList — O(n) contains
}

// ShardManager.java:543-544
boolean shardWasInRecoveredSnapshot = currentSnapshot != null
        && currentSnapshot.getShardList().contains(shardName);

ImmutableList.contains() is O(n) array scan.

Fix

Change shardList storage in ShardManagerSnapshot to ImmutableSet<String>. Rename getShardList() → getShardNames() returning Set<String> (or keep both for compatibility). ImmutableSet.contains() is O(1).

Complexity

Before	After
O(S) per CreateShard	O(1) per CreateShard

Patch

defects/odl/patch/odl-0002-shardmanager-snapshot-shardlist-linear.patch

Unit test

defects/odl/unit/OdlShardManagerSnapshotTest.java

1.7 KiB Raw Blame History