...by using `+ lib.optionalString ...` rather than a substitution. That
way the phases don't have additional trailing white-spaces in the
non-JIT case which cause rebuilds.
Make sure that JIT is actually available when using
services.postgresql = {
enable = true;
enableJIT = true;
package = pkgs.postgresql_15;
};
The current behavior is counter-intuitive because the docs state that
`enableJIT = true;` is sufficient even though it wasn't in that case
because the declared package doesn't have the LLVM dependency.
Fixed by using `package.withJIT` if `enableJIT = true;` and
`package.jitSupport` is `false`.
Also updated the postgresql-jit test to test for that case.
So, patchelf works on ELF files and these don't exist on Darwin. I'm not
aware of any other way to eliminate all references of the executable's
body while preserving library paths in the header. This still works, the
only problem is that darwin has a dependency on llvm.dev, so it's
runtime closure is larger.
This is useful if your postgresql version is dependant on
`system.stateVersion` and not pinned down manually. Then it's not
necessary to find out which version exactly is in use and define
`package` manually, but just stay with what NixOS provides as default:
$ nix-instantiate -A postgresql
/nix/store/82fzmb77mz2b787dgj7mn4a8i4f6l6sn-postgresql-14.7.drv
$ nix-instantiate -A postgresql_jit
/nix/store/qsjkb72fcrrfpsszrwbsi9q9wgp39m50-postgresql-14.7.drv
$ nix-instantiate -A postgresql.withJIT
/nix/store/qsjkb72fcrrfpsszrwbsi9q9wgp39m50-postgresql-14.7.drv
$ nix-instantiate -A postgresql.withJIT.withoutJIT
/nix/store/82fzmb77mz2b787dgj7mn4a8i4f6l6sn-postgresql-14.7.drv
I.e. you can use postgresql with JIT (for complex queries only[1]) like
this:
services.postgresql = {
enable = true;
enableJIT = true;
};
Performing a new override instead of re-using the `_jit`-variants for
that has the nice property that overlays for the original package apply
to the JIT-enabled variant, i.e.
with import ./. {
overlays = [
(self: super: {
postgresql = super.postgresql.overrideAttrs (_: { fnord = "snens"; });
})
];
};
postgresql.withJIT.fnord
still gives the string `snens` whereas `postgresql_jit` doesn't have the
attribute `fnord` in its derivation.
[1] https://www.postgresql.org/docs/current/runtime-config-query.html#GUC-JIT-ABOVE-COST
