nushell/crates/nu-command/src/bytes
Stefan Holderbach a52386e837
Box ShellError in Value::Error (#8375)
# Description

Our `ShellError` at the moment has a `std::mem::size_of<ShellError>` of
136 bytes (on AMD64). As a result `Value` directly storing the struct
also required 136 bytes (thanks to alignment requirements).

This change stores the `Value::Error` `ShellError` on the heap.

Pro:
- Value now needs just 80 bytes
- Should be 1 cacheline less (still at least 2 cachelines)

Con:
- More small heap allocations when dealing with `Value::Error`
  - More heap fragmentation
  - Potential for additional required memcopies

# Further code changes

Includes a small refactor of `try` due to a type mismatch in its large
match.

# User-Facing Changes

None for regular users.

Plugin authors may have to update their matches on `Value` if they use
`nu-protocol`

Needs benchmarking to see if there is a benefit in real world workloads.
**Update** small improvements in runtime for workloads with high volume
of values. Significant reduction in maximum resident set size, when many
values are held in memory.

# Tests + Formatting
2023-03-12 09:57:27 +01:00
..
add.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
at.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
build_.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
bytes_.rs Uniformize usage() and extra_usage() message ending for commands helper. (#8268) 2023-02-28 21:33:02 -08:00
collect.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
ends_with.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
index_of.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
length.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
mod.rs Refactor: introduce general operate commands to reduce duplicate code (#6879) 2022-10-29 16:29:46 -05:00
remove.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
replace.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
reverse.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00
starts_with.rs Box ShellError in Value::Error (#8375) 2023-03-12 09:57:27 +01:00