Having the `post-build-hook` use `nix` from the client package can lead
to a deadlock in case there’s a db migration to do between both, as a
`nix` command running inside the hook will run as root (and as such will
bypass the daemon), so might trigger a db migration, which will get
stuck trying to get a global lock on the DB (as the daemon that ran the
hook already has a lock on it).
When running a `:b` command in the repl, after building the derivations
query the store for its outputs rather than just assuming that they are
known in the derivation itself (which isn’t true for CA derivations)
Fix#5328
This adds an explicit unmount of the store volume to avoid cases
where the installer can hang in await_volume when:
- the user already has a store volume
- that volume is already mounted somewhere other than /nix
- they do not take a path through the installer that results in an
explicit unmount (as both removing and encrypting the volume
would do)
We now parse function applications as a vector of arguments rather
than as a chain of binary applications, e.g. 'substring 1 2 "foo"' is
parsed as
ExprCall { .fun = <substring>, .args = [ <1>, <2>, <"foo"> ] }
rather than
ExprApp (ExprApp (ExprApp <substring> <1>) <2>) <"foo">
This allows primops to be called immediately (if enough arguments are
supplied) without having to allocate intermediate tPrimOpApp values.
On
$ nix-instantiate --dry-run '<nixpkgs/nixos/release-combined.nix>' -A nixos.tests.simple.x86_64-linux
this gives a substantial performance improvement:
user CPU time: median = 0.9209 mean = 0.9218 stddev = 0.0073 min = 0.9086 max = 0.9340 [rejected, p=0.00000, Δ=-0.21433±0.00677]
elapsed time: median = 1.0585 mean = 1.0584 stddev = 0.0024 min = 1.0523 max = 1.0623 [rejected, p=0.00000, Δ=-0.20594±0.00236]
because it reduces the number of tPrimOpApp allocations from 551990 to
42534 (i.e. only small minority of primop calls are partially
applied) which in turn reduces time spent in the garbage collector.
This is in line with XDG Base Directory Specification, where ~/.config is supposed to be used when XDG_CONFIG_HOME is unset.
It also better matches the reality, where ~/.config/nix.conf does not seem to be used.
ShellCheck correctly warns:
In scripts/install-nix-from-closure.sh line 218:
echo -e "\nif [ -e $p ]; then . $p; fi # added by Nix installer" >> "$fn"
^-- SC3037: In POSIX sh, echo flags are undefined.
In scripts/install-nix-from-closure.sh line 229:
echo -e "\nif [ -e $p ]; then . $p; fi # added by Nix installer" >> "$fn"
^-- SC3037: In POSIX sh, echo flags are undefined.
Indeed, this actually breaks on Ubuntu where /bin/sh is dash.
Fixes#5458.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
