Packed vs Struct comparison

FlatMessage supports two types of nested structures, each with different characteristics and compatibility behaviors: FlatMessageStruct and FlatMessagePacked. To test the performance of these two types, we can use the following structure:

#![allow(unused)]
fn main() {
pub struct InnerStruct {
    s1: String,
    s2: String,
    v1: u32,
    v2: u64,
    arr: Vec<u32>,
}

pub struct NestedStruct {
    field: InnerStruct,
}
}

with the following settings (which will be used in the benchmarks):

1. For FlatMessageStruct:

   #![allow(unused)]
   fn main() {
   #[derive(FlatMessageStruct)]
   pub struct InnerStruct { ... }
   
   #[derive(FlatMessage)]
   pub struct NestedStruct {
       #[flat_message_item(kind = struct, align = 4)]
       field: InnerStruct,
   }
   }

2. For FlatMessagePacked:

   #![allow(unused)]
   fn main() {
   #[derive(FlatMessagePacked)]
   pub struct InnerStruct { ... }
   
   #[derive(FlatMessage)]
   pub struct NestedStruct {
       #[flat_message_item(kind = packed, align = 4)]
       field: InnerStruct,
   }
   }

Test specs

• Iterations: k = 10
• Serialization and deserialization repetitions / iteration: n = 1000000
• Data size: 161 bytes

Results

1. Windows Execution

2. MacOS Execution

3. Linux Execution