Use a sidecar connection per PHP thread#3770
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🎉 All green!❄️ No new flaky tests detected 🎯 Code Coverage (details) 🔗 Commit SHA: 472579b | Docs | Datadog PR Page | Was this helpful? React with 👍/👎 or give us feedback! |
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Leiyks
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While the sidecar has been a process global for the longest time, it's also unfair with respect to limits and not compatible with the newly introduced outbox. Having a connection per thread ensures that every thread can have up to 100 queued items. It also reduces contention on the SidecarTransport, which was indeed adding quite a bit of latency due to threads accumulating in futex_wait for very short requests under moderate load. Moving the background sender stats to its own thread in preparation of dropping the Mutex on the SidecarTransport fully. Signed-off-by: Bob Weinand <bob.weinand@datadoghq.com>
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Benchmarks [ tracer ]Benchmark execution time: 2026-04-17 13:42:19 Comparing candidate commit fd34daf in PR branch Found 1 performance improvements and 1 performance regressions! Performance is the same for 191 metrics, 1 unstable metrics. scenario:MessagePackSerializationBench/benchMessagePackSerialization-opcache
scenario:PHPRedisBench/benchRedisOverhead
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Signed-off-by: Bob Weinand <bob.weinand@datadoghq.com>
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While the sidecar has been a process global for the longest time, it's also unfair with respect to limits and not compatible with the newly introduced outbox.
Having a connection per thread ensures that every thread can have up to 100 queued items. It also reduces contention on the SidecarTransport, which was indeed adding quite a bit of latency due to threads accumulating in futex_wait for very short requests under moderate load.
Moving the background sender stats to its own thread in preparation of dropping the Mutex on the SidecarTransport fully.