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+Major optimization of the Durable Sessions feature.
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+
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+- Idle durable subscribers no longer consume CPU.
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+- End-to-end latency of durable sessions has been improved.
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+- Frequency of durable storage queries has been significantly reduced.
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+- Optimized utilization of the cluster backplane network.
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+
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+Configuration changes:
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+
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+- Meaning of `durable_sessions.idle_poll_interval` parameter has changed.
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+ Now durable sessions are waken up immediately when new messages are written to the durable storage,
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+ so `idle_poll_interval` no longer affects end-to-end latency during normal operation.
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+
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+ From EMQX 5.8.1 on, idle polling is only used as a fallback mechanism for recovering from certain network errors.
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+ Therefore, the default value of `idle_poll_interval` has been increased.
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+ If this parameter has been customized in a previous version of EMQX, it should be increased as well.
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+
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+New metrics:
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+
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+- `emqx_ds_poll_requests`
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+- `emqx_ds_poll_requests_fulfilled`
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+- `emqx_ds_poll_requests_dropped`
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+- `emqx_ds_poll_requests_expired`
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+- `emqx_ds_poll_request_sharing`
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ieQu1