this is only used to close non-stdio files in derivation sandboxes. we
may as well encode that in its name, drop the unnecessary integer set,
and use close_range to deal with the actual closing of files. not only
is this clearer, it also makes sandbox setup on linux fast by 1ms each
(cherry-picked and adapted from
c7d97802e4)
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Co-authored-by: Cole Helbling <cole.e.helbling@outlook.com>
Co-authored-by: John Ericson <git@JohnEricson.me>
Starting in macOS 15 Sequoia, macOS daemon UIDs are encroaching on our
default UIDs of 301-332. This commit relocates our range up to avoid
clashing with the current UIDs of 301-304 and buy us a little time
while still leaving headroom for people installing more than 32 users.
Since withFramedSink() is now used a lot more than in the past (for
every addToStore() variant), we were creating a lot of threads, e.g.
nix flake show --no-eval-cache --all-systems github:NixOS/nix/afdd12be5e19c0001ff3297dea544301108d298
would create 46418 threads. While threads on Linux are cheap, this is
still substantial overhead.
So instead, just poll from FramedSink before every write whether there
are pending messages from the daemon. This could slightly increase the
latency on log messages from the daemon, but not on exceptions (which
were only synchronously checked from FramedSink anyway).
This speeds up the command above from 19.2s to 17.5s on my machine (a
9% speedup).
Fixes
```
umount: /tmp/nix-shell.i3xRwX/nix-test/local-overlay-store/delete-refs/stores/merged-store/nix/store: filesystem was unmounted, but failed to update userspace mount table.
make: *** [mk/lib.mk:93: tests/functional/local-overlay-store/delete-refs.sh.test] Error 16
```
in a dev shell.
Note: this previously worked before we didn't have umount in the dev
shell, so we got /run/wrappers/bin/umount.
Incorrectly high expectations lead to frustration for users who
stick around to experience how useless it is for e.g. a devShell
https://functional.cafe/@arianvp/112976284363120036:
> Flakes doesn't have eval caching. It has command line argument
> caching. It literally just stores the cli argument you passed
> in a sqlite database and yes that's as useless as it sounds
> When I discovered flakes had no expression level caching whatsoever
> I kind of felt lied to and betrayed.
Fixes
```
GEN /home/eelco/Dev/nix-master/outputs/out/share/doc/nix/manual/index.html
error: File not found: ../store/types/
┌─ release-notes/rl-next.md:60:197
│
60 │ The build hook protocol did in principle support custom ways of remote building, but that can also be accomplished with a custom service for the ssh or daemon/ssh-ng protocols, or with a custom [store type](../store/types/) i.e. `Store` subclass. <!-- we normally don't mention classes, but consider that this release note is about a library use case -->
│ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File not found: ../store/types/
Error: One or more incorrect links
2024-08-19 16:47:57 [ERROR] (mdbook::renderer): Renderer exited with non-zero return code.
2024-08-19 16:47:57 [ERROR] (mdbook::utils): Error: Rendering failed
2024-08-19 16:47:57 [ERROR] (mdbook::utils): Caused By: The "linkcheck" renderer failed
```
`make check` was reverted too soon. The hacking guide wasn't brought
up to date with the new workflow, and it's not clear how to use
meson for everything.
This reverts commit 6f3045c2a2.
