vole

Clone

Read only, no credentials:

https://rodent.software/vole.git

Write over SSH with a registered key:

git clone ssh://git@rodent.software:2222/vole.git

A free and open-source forge that lives in your Git repo.

Phase 4: one repository may be bounded, and a freed slot wakes the parked

8d33608319bb83725256d02196925309fe521cda · Keenan Nemetz · 17d ago · parent 379dad1e

Phase 4: one repository may be bounded, and a freed slot wakes the parked

max_jobs_per_repo caps how many of one repository's jobs run at once; unset
there is still no cap. Ordering and bounding answer different questions: the
lease already serves the least busy repository first, which stops a burst
taking the whole fleet, but ordering is not a bound — and what an operator
wants when one repository's build saturates the instance is a number.

A repository at its cap is skipped rather than blocking, so the other
repositories an account may run are still served. That makes nil from the
lease mean two things: "nothing to do", and "work exists, but not for you
yet". The second meaning is why Finish now wakes the parked lease — releasing
a slot is work somebody can pick up, and without it a runner parked on a cap
would sit out its whole wait against a queue it could already have taken.
Both are one line of the same query: `? = 0 OR COALESCE(busy.n, 0) < ?`, so
"no cap" does not become a second query string that can drift.

The runners page renders `4 of 4 (at the cap)` beside the depth, because a
queue that is full and not draining is exactly the question that page exists
to answer: "7 waiting, 4 running" is a mystery where the cap is not shown.

Measured: TestPerRepoCapBoundsOneRepositoryAndResumesWhenASlotFrees puts two
jobs in each of two repositories with a cap of 1, so "nothing to lease"
cannot be confused with "no work" — both repositories served once, a third
runner refused, a finish waking the parked lease and the freed slot's own
repository becoming leasable. TestRunnersPageSaysWhenARepositoryIsAtItsCap
and TestMaxJobsPerRepoLoads cover the page and the key.

internal/config/config_test.go +33

@@ -0,0 +1,33 @@
	1	package config
	2
	3	import (
	4	"os"
	5	"path/filepath"
	6	"testing"
	7	)
	8
	9	// A mistyped TOML tag does not fail anything: the key is simply ignored and the
	10	// default applies, which is invisible until somebody's cap does nothing. So the one
	11	// setting whose absence is a silent policy change is pinned here.
	12	func TestMaxJobsPerRepoLoads(t *testing.T) {
	13	path := filepath.Join(t.TempDir(), "vole.toml")
	14	if err := os.WriteFile(path, []byte("max_jobs_per_repo = 3\n"), 0o644); err != nil {
	15	t.Fatal(err)
	16	}
	17	c, err := Load(path)
	18	if err != nil {
	19	t.Fatal(err)
	20	}
	21	if c.MaxJobsPerRepo != 3 {
	22	t.Fatalf("MaxJobsPerRepo = %d, want 3", c.MaxJobsPerRepo)
	23	}
	24
	25	// Absent means no bound, which is the behaviour before the key existed.
	26	unset, err := Load("")
	27	if err != nil {
	28	t.Fatal(err)
	29	}
	30	if unset.MaxJobsPerRepo != 0 {
	31	t.Fatalf("default = %d, want 0 (no cap)", unset.MaxJobsPerRepo)
	32	}
	33	}