Struct RenameWithRetryStrategy 

pub struct RenameWithRetryStrategy {}

RenameWithRetryStrategy uses the Standard Library rename function to transition the working file to the target file and retries if that fails with a PermissionDenied error.

The other commit strategy available is SimpleRenameStrategy.

For POSIX systems and Windows systems in which there is no contention for the target file, SimpleRenameStrategy is a good choice. For Windows systems in which two or more threads are simultaneously trying to update the target, RenameWithRetryStrategy is a good choice.

This crate provides a ready-to-use RenameWithRetryStrategy instance named RENAME_WITH_RETRY_STRATEGY.

By default, the SimpleRenameStrategy commit strategy is used.

This retry strategy has been shown to work well with Windows 10 and Windows 11 on local SSD drives and with a NAS using as many as 10 threads contending for the target file…

• Use a “jitter” between 0 and 15 to avoid threads being synchronized during contention
• Calculate a “base sleep” value: 11 + (3 * jitter)
• Try to commit
• If that succeeds then we’re done
• If that fails with any error except PermissionDenied then return that error
• Otherwise sleep for the base sleep value multiplied by the try count. For example…
  • If the jitter is 1
  • Then the base sleep is 11 + (3 * 1) = 14
  • For the first try, this strategy would sleep for 14 * 1 milliseconds
  • For the second try, this strategy would sleep for 14 * 2 milleconds
• Until 7 attempts have been made at which point the PermissionDenied error is returned.

In the worst case, this strategy sleeps for a total of (11 + (3 * 15)) * (7 * (7+1) / 2) = 1568 milliseconds.

Example

use phazer::{PhazerBuilder, RENAME_WITH_RETRY_STRATEGY};

fn main() -> Result<(), Box<dyn std::error::Error>> {

    let phazer = PhazerBuilder::with_target("uses-rename-with-retry-strategy.txt")
        .commit_strategy(RENAME_WITH_RETRY_STRATEGY)
        .build();

    // Build the working file

    // `rename` is called to transition the working file to the target
    phazer.commit()?;

    Ok(())
}

Trait Implementations

impl Default for RenameWithRetryStrategy

fn default() -> Self

Returns the “default value” for a type.