Hi,
cargo.eclass is one of the slowest eclasses in ::gentoo, and does some
pretty heavy processing in global scope. Here's a series of patches
to optimize its behavior.
Unfortunately, the optimizations cannot be done without changing
the API. However, the series preserves backwards compatibility --
existing ebuilds will simply remain slower.
The two main changes are:
1. Replacing subshell-based `$(cargo_crate_uris)` with global variable
`${CARGO_CRATE_URIS}`. This requires that `CRATES` and `GIT_CRATES`
are defined prior to inherit -- this was already the case
for the former, and only one case of `GIT_CRATES` does not conform.
If they're not, then the variable will simply be empty but the old
function will still work.
2. Supporting separate crate names from versions using a forward slash
rather than a hyphen. This makes it possible to parse the crate list
using a simple cutting rather than regular expressions. Again,
existing syntax continues working but it remains much slower.
To compare, the initial timings for the eclass give, using the 52 CRATES
from dev-python/cryptography:
real 252 it/s
user 289 it/s
While the timings for fully optimized form (using variable and slashes)
give:
real 952 it/s
user 952 it/s
--
Best regards,
Michał Górny
Michał Górny (5):
eclass/tests: Add a minimal benchmark for cargo.eclass
cargo.eclass: Add variable alternative to $(cargo_crate_uris)
cargo.eclass: Optimize GIT_CRATES check
cargo.eclass: Support separating crate names/versions via slash
cargo.eclass: Mark GIT_CRATES as pre-inherit
eclass/cargo.eclass | 127 ++++++++++++++++++++++--------------
eclass/tests/cargo-bench.sh | 114 ++++++++++++++++++++++++++++++++
2 files changed, 192 insertions(+), 49 deletions(-)
create mode 100755 eclass/tests/cargo-bench.sh
--
2.41.0
