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ScyllaDB Docs Scylla Rust Driver Speculative execution Percentile speculative execution

Percentile speculative execution¶

This policy has access to Metrics shared with session, and triggers speculative execution when the request to the current host is above a given percentile.

Example¶

To use this policy in Session:

use std::{sync::Arc, time::Duration};
use scylla::{
    Session,
    SessionBuilder,
    speculative_execution::PercentileSpeculativeExecutionPolicy,
    transport::execution_profile::ExecutionProfile,
};

let policy = PercentileSpeculativeExecutionPolicy  {
    max_retry_count: 3,
    percentile: 99.0,
};

let handle = ExecutionProfile::builder()
    .speculative_execution_policy(Some(Arc::new(policy)))
    .build()
    .into_handle();

let session: Session = SessionBuilder::new()
    .known_node("127.0.0.1:9042")
    .default_execution_profile_handle(handle)
    .build()
    .await?;
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  • Percentile speculative execution
    • Example
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Last updated on 22 March 2023.
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