Sergei Zimmerman 8708e9a526 libutil: Use caching directory_entry API in PosixSourceAccessor::readDirectory ... Previous use of symlink_status() always translated into a stat call, leading to huge performance penalties for by-name-overlay in nixpkgs. The comment below references the possible caching, but that seemed to be erroneous, since the correct way to make use of the caching API is by calling a bunch of `is_*` functions [1]. For example, here's how libstdc++ does that [2], [3]. This translates to great nixpkgs eval performance improvements: ``` Benchmark 1: GC_INITIAL_HEAP_SIZE=4G result/bin/nix-instantiate ../nixpkgs -A hello --readonly-mode Time (mean ± σ): 186.7 ms ± 6.7 ms [User: 121.3 ms, System: 64.9 ms] Range (min … max): 179.4 ms … 201.6 ms 16 runs Benchmark 2: GC_INITIAL_HEAP_SIZE=4G nix-instantiate ../nixpkgs -A hello --readonly-mode Time (mean ± σ): 230.6 ms ± 5.0 ms [User: 126.9 ms, System: 103.1 ms] Range (min … max): 225.1 ms … 241.4 ms 13 runs ``` [1]: https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0317r1.html [2]: 8ea555b7b4/libstdc%2B%2B-v3/include/bits/fs_dir.h (L341-L348) [3]: 8ea555b7b4/libstdc%2B%2B-v3/include/bits/fs_dir.h (L161-L163)		2025-06-30 23:29:07 +03:00
..
freebsd	Restore multiline formatting of lists in meson files	2025-06-20 23:12:36 +03:00
include/nix/util	Replace 'bool sync' with an enum for clarity	2025-06-22 16:48:34 +02:00
linux	Restore multiline formatting of lists in meson files	2025-06-20 23:12:36 +03:00
signature	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
unix	Fix various typos in source code	2025-05-25 20:14:11 +00:00
widecharwidth	try to calculate character width	2024-12-28 12:01:32 +01:00
windows	Restore multiline formatting of lists in meson files	2025-06-20 23:12:36 +03:00
.version	Build nix-util with Meson	2024-06-12 18:31:02 -04:00
archive.cc	Use StringMap instead of std::map<std::string, std::string> throughout the codebase	2025-05-19 20:33:28 +00:00
args.cc	treewide: Use StringSet alias consistently instead of std::set<std::string>	2025-05-02 17:40:29 +00:00
canon-path.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
compression.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
compute-levels.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
config-global.cc	Simplify ConfigRegistrations	2025-05-05 09:42:16 +02:00
configuration.cc	treewide: Use StringSet alias consistently instead of std::set<std::string>	2025-05-02 17:40:29 +00:00
current-process.cc	Prepare for FreeBSD sandboxing support	2025-05-27 14:54:50 -04:00
english.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
environment-variables.cc	Use StringMap instead of std::map<std::string, std::string> throughout the codebase	2025-05-19 20:33:28 +00:00
error.cc	libutil: Use std::shared_ptr<const Pos> instead of std::shared_ptr<Pos>	2025-06-01 20:55:26 +00:00
executable-path.cc	Drop fs alias in favour of std::filesystem	2025-05-01 14:24:34 +02:00
exit.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
experimental-features.cc	Rework future tense in user-facing messages	2025-06-12 09:07:36 -07:00
file-content-address.cc	Replace 'bool sync' with an enum for clarity	2025-06-22 16:48:34 +02:00
file-descriptor.cc	Drop guessOrInventPathFromFD()	2025-06-22 16:48:34 +02:00
file-system.cc	Replace 'bool sync' with an enum for clarity	2025-06-22 16:48:34 +02:00
fs-sink.cc	Add -Wundef to make #if FOO an error if not defined	2025-04-05 00:45:19 +02:00
git.cc	libutil: Use correct argument to Error format ctor	2025-04-24 22:27:03 +00:00
hash.cc	Fix various typos in source code	2025-05-25 20:14:11 +00:00
hilite.cc	Fix various typos in source code	2025-05-25 20:14:11 +00:00
json-utils.cc	bugfix in getInteger(const nlohmann::json &) and add bounds checks	2025-04-30 01:38:48 +02:00
logging.cc	libutil: Use std::shared_ptr<const Pos> instead of std::shared_ptr<Pos>	2025-06-01 20:55:26 +00:00
memory-source-accessor.cc	Clear displayPrefix in makeEmptySourceAccessor	2025-05-29 19:35:12 +00:00
meson.build	Drop guessOrInventPathFromFD()	2025-06-22 16:48:34 +02:00
meson.options	Build nix-util with Meson	2024-06-12 18:31:02 -04:00
mounted-source-accessor.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
nix-meson-build-support	rename: build-utils-meson -> nix-meson-build-support	2024-12-09 16:54:42 +01:00
package.nix	Fix FreeBSD builds	2025-05-28 12:47:33 -04:00
pos-table.cc	libexpr: Actually cache line information in PosTable	2025-05-15 23:07:25 +00:00
position.cc	libutil: Use std::shared_ptr<const Pos> instead of std::shared_ptr<Pos>	2025-06-01 20:55:26 +00:00
posix-source-accessor.cc	libutil: Use caching directory_entry API in PosixSourceAccessor::readDirectory	2025-06-30 23:29:07 +03:00
references.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
serialise.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
source-accessor.cc	cherry-pick https://gerrit.lix.systems/c/lix/+/2100	2025-05-21 08:49:09 -07:00
source-path.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
strings.cc	treewide: Use StringSet alias consistently instead of std::set<std::string>	2025-05-02 17:40:29 +00:00
subdir-source-accessor.cc	Store::getFSAccessor: Do not include the store dir	2025-04-09 17:34:18 -04:00
suggestions.cc	treewide: Use StringSet alias consistently instead of std::set<std::string>	2025-05-02 17:40:29 +00:00
tarfile.cc	Merge pull request #13175 from xokdvium/optimise-fetchtarball	2025-05-13 14:21:26 +02:00
tee-logger.cc	Add json-log-path setting	2025-05-23 10:45:12 +02:00
terminal.cc	libutil: amend OSC 8 escape stripping for xterm-style separator	2025-04-29 16:12:18 +01:00
thread-pool.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
union-source-accessor.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
unix-domain-socket.cc	Fix mingw build	2025-05-28 00:48:10 +02:00
url.cc	Use StringMap instead of std::map<std::string, std::string> throughout the codebase	2025-05-19 20:33:28 +00:00
users.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00
util.cc	Rename shellEscape -> escapeShellArgAlways	2025-04-23 22:56:07 +02:00
xml-writer.cc	Expose the nix component in header include paths	2025-04-01 11:40:42 -04:00