Make max_bytes_per_stream optional in config

[allada]

Defaults "max_bytes_per_stream" to 64Kib in config file.

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This change is 

[allada]

+@adam-singer

Reviewable status: 0 of 10 files reviewed, all discussions resolved (waiting on @adam-singer)

[adam-singer]

Reviewed 10 of 10 files at r1, all commit messages.
Reviewable status: all files reviewed, 3 unresolved discussions (waiting on @allada)

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nativelink-config/src/cas_server.rs line 126 at r1 (raw file):

    /// 16KiB - 64KiB is optimal.
    ///
    /// Defaults: 64Kib

nit: 64Kib -> 64KiB

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nativelink-config/src/cas_server.rs line 128 at r1 (raw file):

    /// Defaults: 64Kib
    #[serde(default, deserialize_with = "convert_numeric_with_shellexpand")]
    pub max_bytes_per_stream: usize,

What happens with serialization here if parses for a size larger than machine architecture (given usize is machine size specific)?

It does seem the least bad choice to keep ubiquitous between specific size, wondering if configuration mishaps could happen here (and think probably very low)

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nativelink-service/src/bytestream_server.rs line 176 at r1 (raw file):

            stores.insert(instance_name.to_string(), store);
        }
        let max_bytes_per_stream = if config.max_bytes_per_stream == 0 {

Are there any maximum value constraints that we should guard here on? A size that might have the opposite regardless of situation?

[allada]

Reviewable status: 9 of 10 files reviewed, 1 unresolved discussion (waiting on @adam-singer)

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nativelink-config/src/cas_server.rs line 126 at r1 (raw file):

Previously, adam-singer (Adam Singer) wrote…

nit: 64Kib -> 64KiB

Done.

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nativelink-config/src/cas_server.rs line 128 at r1 (raw file):

Previously, adam-singer (Adam Singer) wrote…

What happens with serialization here if parses for a size larger than machine architecture (given usize is machine size specific)?

It does seem the least bad choice to keep ubiquitous between specific size, wondering if configuration mishaps could happen here (and think probably very low)

I'm pretty sure it'll panic at parse time. Rust has undefined behavior protection even at runtime (in theory).

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nativelink-service/src/bytestream_server.rs line 176 at r1 (raw file):

Previously, adam-singer (Adam Singer) wrote…

Are there any maximum value constraints that we should guard here on? A size that might have the opposite regardless of situation?

In theory the maximum is how much ram you have. This is a config value, so it's generally considered a "safe" variable since it's a config set by the server and not a property sent by a user.

[allada]

Dismissed @adam-singer from a discussion.
Reviewable status: 9 of 10 files reviewed, all discussions resolved (waiting on @adam-singer)