diff --git a/go/buildcpu/buildcpu.go b/go/buildcpu/buildcpu.go index 4df094e..06b9dec 100644 --- a/go/buildcpu/buildcpu.go +++ b/go/buildcpu/buildcpu.go @@ -1,94 +1,50 @@ // Package buildcpu is how much of a build node's processors its builds may take, and how they yield to everything else -// there (novox/hq issue 1806; the operator, 2026-10-26: "limit CPU usage on our build nodes so the total cpu usage never -// impacts the normal workings of our nodes"). +// there (novox/hq ADR 0553, issue 1806; the operator, 2026-10-26: "limit CPU usage on our build nodes so the total cpu +// usage never impacts the normal workings of our nodes ... We have 3 build agents so they should share the cpu power"). // // Three parts, each with one owner: // -// - **Priority.** A build seat's holder (catalogue.Seat.Yields) runs at the lowest CPU and IO priority there is: the -// composer gives its runtime process declaration.Yields, and the node-engine writes it into the unit as -// CPUWeight=idle, IOWeight=1, Nice=19 and the best-effort IO class at its lowest level. Interactive and service -// work always comes first; builds take the cycles nothing else wants. -// - **The cap.** The build modules' setting `cpu-cap` (Setting) gives each node the share of its processors its builds -// may take at most, as `=` pairs. The composer turns this node's share into Yields.CPUShare, and the -// node-engine into CPUQuota for the machine's processor count: a hard bound, held by the kernel. -// - **Threads.** Inside that bound a step starts no more threads than its part of it (Threads): GOMAXPROCS, `go -// test -p`, the Node test runner's concurrency. A step with more runnable threads than its quota only waits in the -// kernel's throttle, and its timeouts with it. +// - **Priority.** A build seat's holder (catalogue.Seat.Yields) runs at the lowest priority there is: the composer +// gives its runtime process declaration.Yields, and the node-engine places every yielding process of the node in +// one slice (declaration.YieldSlice) whose CPU weight is idle, with Nice=19 for every process it starts. +// Interactive and service work always comes first; builds take the cycles nothing else wants. +// - **One cap per node, shared.** The node's share of its processors is one value, the node-tools runtime's setting +// `build-cpu-share` (ShareSetting), set per node through the node's settings layer. The node-engine writes it as the +// slice's CPUQuota: one bound the kernel holds for all the node's build modules together, never one per module. +// - **Threads.** Inside that bound a step starts no more threads than its part of it (Threads): the node's share +// divided by every build slot of the node, across all its build modules (the composer hands both as words, +// ShareWord and SlotsWord). GOMAXPROCS sets every go command's -p, the compiler's concurrency, a test binary's +// processors and -parallel. package buildcpu import ( - "fmt" "os" "runtime" - "sort" "strconv" "strings" ) -// Setting is the build modules' setting of each node's processor cap: `=` pairs separated by commas, -// such as `shanks=50,ace=75`; a percent sign after the number is allowed. Each build module declares it with Defaults -// as its default. -const Setting = "cpu-cap" +// ShareSetting is the node-tools runtime's setting of the node's processor share for its builds, in percent of the +// machine's processors, 1 to 100: one value per node, set through the node's settings layer (novox/hq ADR 0553 §3). +const ShareSetting = "build-cpu-share" -// Defaults is the setting's default: the operator's two desktops (shanks, g14) keep half their processors for -// themselves at all times, and ace, a server, builds on three quarters. A node it does not name has DefaultPercent. -const Defaults = "shanks=50,g14=50,ace=75" - -// DefaultPercent is the cap of a node the setting does not name. +// DefaultPercent is the share where nothing sets one: half the machine, so a desktop keeps half its processors for +// itself whatever builds. const DefaultPercent = 50 -// Parse reads the setting's pairs. A percent outside 1 to 100 is refused: 0 would stop every build without pausing the -// seat (the capacity setting says that, with 0 asks), and more than 100 is no cap. -func Parse(s string) (map[string]int, error) { - out := map[string]int{} - for _, pair := range strings.Split(s, ",") { - pair = strings.TrimSpace(pair) - if pair == "" { - continue - } - node, value, ok := strings.Cut(pair, "=") - node = strings.TrimSpace(node) - value = strings.TrimSuffix(strings.TrimSpace(value), "%") - n, err := strconv.Atoi(strings.TrimSpace(value)) - if !ok || node == "" || err != nil || n < 1 || n > 100 { - return nil, fmt.Errorf("the processor cap %q is not =", pair) - } - if _, dup := out[node]; dup { - return nil, fmt.Errorf("the processor cap names %s twice", node) - } - out[node] = n - } - return out, nil -} +// BuildSeats is how many seats yield (catalogue.Seat.Yields): one build module per language. A step that is told no +// node-wide slot count assumes every one of them runs its full capacity beside it. +const BuildSeats = 3 -// Of is node's cap in percent of its processors: DefaultPercent for a node the setting does not name. -func Of(setting, node string) (int, error) { - caps, err := Parse(setting) - if err != nil { - return 0, err - } - if n, ok := caps[node]; ok { - return n, nil - } - return DefaultPercent, nil -} +// The words the composer gives every yielding module (novox/hq ADR 0553 §4): the node's share, and every build slot +// of the node across all its yielding modules. +const ( + ShareWord = "MESH_BUILD_CPU_SHARE" + SlotsWord = "MESH_BUILD_SLOTS" +) -// Format is a cap map in the setting's own words, sorted by node. -func Format(caps map[string]int) string { - nodes := make([]string, 0, len(caps)) - for n := range caps { - nodes = append(nodes, n) - } - sort.Strings(nodes) - parts := make([]string, 0, len(nodes)) - for _, n := range nodes { - parts = append(parts, fmt.Sprintf("%s=%d", n, caps[n])) - } - return strings.Join(parts, ",") -} - -// Quota is the unit's CPUQuota for a share of a machine with cores processors: systemd counts a quota in percent of -// one processor, so half of 24 is 1200%. At least 100%, one processor, so a cap on a small machine never stops a step. +// Quota is a CPUQuota for a share of a machine with cores processors: systemd counts a quota in percent of one +// processor, so half of 24 is 1200%. At least 100%, one processor, so a share on a small machine never stops a step. func Quota(percent, cores int) int { q := percent * cores if q < 100 { @@ -97,14 +53,14 @@ func Quota(percent, cores int) int { return q } -// Threads is how many threads one step may run at once: its part of the cap when slots steps run beside it, at least -// one. Rounded down, so the steps together stay inside the quota. +// Threads is how many threads one step may run at once: its part of the share when slots steps may run on the node +// at once, at least one. Rounded down, so the steps together stay inside the quota. func Threads(percent, cores, slots int) int { if slots < 1 { slots = 1 } if percent < 1 || percent > 100 { - percent = 100 + percent = DefaultPercent } t := cores * percent / 100 / slots if t < 1 { @@ -115,28 +71,36 @@ func Threads(percent, cores, slots int) int { // Limits is what one step is held to on this node, as a status tool says it. type Limits struct { - // Percent is the node's cap in percent of its processors, and Setting the words it came from. - Percent int `json:"cap-percent"` - Setting string `json:"cap-setting"` + // Percent is the node's share in percent of its processors; From says where it was read: the composer's word, + // or the default. + Percent int `json:"share-percent"` + From string `json:"share-from"` // Cores is the machine's processor count. Cores int `json:"cores"` - // Slots is the node's build capacity: steps at once. - Slots int `json:"slots"` + // Slots is every build slot of the node, across all its build modules; SlotsFrom where it was read. + Slots int `json:"node-slots"` + SlotsFrom string `json:"slots-from"` // Threads is what each step is given (Threads). Threads int `json:"threads-per-step"` } -// LimitsFor is the limits of a step on node, from the cap setting and the node's capacity. A setting that cannot be read -// gives the default cap and says why in the error, so a step still runs with a bound rather than none. -func LimitsFor(setting, node string, slots int) (Limits, error) { - l := Limits{Setting: setting, Cores: runtime.NumCPU(), Slots: slots} - p, err := Of(setting, node) - if err != nil { - p = DefaultPercent +// FromWords is the limits of a step from the words the composer gave this process (ShareWord, SlotsWord). Where a word +// is absent or not a number: the default share, and own × BuildSeats slots. A module told nothing assumes every build +// module of the node runs its full capacity beside it, so the steps together never take more than the default share. +func FromWords(getenv func(string) string, own int) Limits { + if own < 1 { + own = 1 } - l.Percent = p - l.Threads = Threads(p, l.Cores, slots) - return l, err + l := Limits{Percent: DefaultPercent, From: "default", Cores: runtime.NumCPU(), Slots: own * BuildSeats, + SlotsFrom: "own capacity × " + strconv.Itoa(BuildSeats) + " build seats"} + if n, err := strconv.Atoi(strings.TrimSpace(getenv(ShareWord))); err == nil && n >= 1 && n <= 100 { + l.Percent, l.From = n, ShareWord + } + if n, err := strconv.Atoi(strings.TrimSpace(getenv(SlotsWord))); err == nil && n >= 1 { + l.Slots, l.SlotsFrom = n, SlotsWord + } + l.Threads = Threads(l.Percent, l.Cores, l.Slots) + return l } // Env is the environment a step's commands are given so they start no more threads than they may: GOMAXPROCS for every @@ -150,32 +114,30 @@ func Env(threads int) []string { return []string{"GOMAXPROCS=" + t, "UV_THREADPOOL_SIZE=" + t} } -// WithEnv is env with Env(threads) in place of any GOMAXPROCS or UV_THREADPOOL_SIZE it carried. -func WithEnv(env []string, threads int) []string { - out := make([]string, 0, len(env)+2) - for _, kv := range env { - if strings.HasPrefix(kv, "GOMAXPROCS=") || strings.HasPrefix(kv, "UV_THREADPOOL_SIZE=") { - continue - } - out = append(out, kv) - } - return append(out, Env(threads)...) +// InForce is what the kernel holds this process to, read rather than assumed (evidence over assertion): its nice +// level, its cgroup (the unit) and the cgroup's parent (the slice the node-engine placed it in), each one's CPU weight, +// idle mark and quota. A field the machine does not answer is left empty and Unread says which. +// +// The IO weight is read but binds only where the disk's scheduler honours it (bfq, or the io.cost controller); under +// the scheduler `none`, the usual one for NVMe, it does nothing, and the CPU bound is what holds. +type InForce struct { + Nice int `json:"nice"` + Cgroup string `json:"cgroup,omitempty"` + Unit Group `json:"unit"` + Slice Group `json:"slice"` + // Quota is the tighter of the two groups' cpu.max as a percent of one processor, 0 with none. + Quota int `json:"quota-percent,omitempty"` + Unread []string `json:"unread,omitempty"` } -// InForce is what the kernel holds this process to, read rather than assumed (evidence over assertion): its nice -// level, its cgroup, the cgroup's CPU weight, idle mark and quota. A field the machine does not answer is left empty -// and Unread says which. -type InForce struct { - Nice int `json:"nice"` - Cgroup string `json:"cgroup,omitempty"` +// Group is one cgroup's controls. +type Group struct { + Path string `json:"path,omitempty"` CPUIdle string `json:"cpu-idle,omitempty"` CPUWeight string `json:"cpu-weight,omitempty"` // CPUMax is the cgroup's cpu.max: " ", or "max" with no quota. - CPUMax string `json:"cpu-max,omitempty"` - // Quota is CPUMax as a percent of one processor, 0 with none. - Quota int `json:"quota-percent,omitempty"` - IOWeight string `json:"io-weight,omitempty"` - Unread []string `json:"unread,omitempty"` + CPUMax string `json:"cpu-max,omitempty"` + IOWeight string `json:"io-weight,omitempty"` } // cgroupRoot is where the unified hierarchy is mounted. A variable so a test can point it elsewhere. @@ -184,6 +146,9 @@ var cgroupRoot = "/sys/fs/cgroup" // procSelfCgroup is this process's cgroup file. A variable so a test can point it elsewhere. var procSelfCgroup = "/proc/self/cgroup" +// procSelfStat is this process's stat file. A variable so a test can point it elsewhere. +var procSelfStat = "/proc/self/stat" + // ReadInForce reads what the kernel holds this process to. func ReadInForce() InForce { var f InForce @@ -202,20 +167,28 @@ func ReadInForce() InForce { f.Unread = append(f.Unread, "cgroup: not on the unified hierarchy") return f } - dir := cgroupRoot + f.Cgroup - read := func(name string) string { - b, err := os.ReadFile(dir + "/" + name) - if err != nil { - f.Unread = append(f.Unread, name+": "+err.Error()) - return "" + read := func(path string) Group { + g := Group{Path: path} + value := func(name string) string { + b, err := os.ReadFile(cgroupRoot + path + "/" + name) + if err != nil { + f.Unread = append(f.Unread, path+"/"+name+": "+err.Error()) + return "" + } + return strings.TrimSpace(string(b)) + } + g.CPUIdle, g.CPUWeight, g.CPUMax, g.IOWeight = value("cpu.idle"), value("cpu.weight"), value("cpu.max"), value("io.weight") + return g + } + f.Unit = read(f.Cgroup) + if i := strings.LastIndex(f.Cgroup, "/"); i > 0 { + f.Slice = read(f.Cgroup[:i]) + } + for _, q := range []int{quotaOf(f.Unit.CPUMax), quotaOf(f.Slice.CPUMax)} { + if q > 0 && (f.Quota == 0 || q < f.Quota) { + f.Quota = q } - return strings.TrimSpace(string(b)) } - f.CPUIdle = read("cpu.idle") - f.CPUWeight = read("cpu.weight") - f.CPUMax = read("cpu.max") - f.IOWeight = read("io.weight") - f.Quota = quotaOf(f.CPUMax) return f } @@ -233,9 +206,6 @@ func quotaOf(cpuMax string) int { return q * 100 / p } -// procSelfStat is this process's stat file. A variable so a test can point it elsewhere. -var procSelfStat = "/proc/self/stat" - // nice is this process's nice level from its stat file (the 19th field, counted after the command's closing // parenthesis, which may itself hold spaces); 0 when it cannot be read. func nice() int { diff --git a/go/buildcpu/buildcpu_test.go b/go/buildcpu/buildcpu_test.go index 8c36ddb..cdf7b91 100644 --- a/go/buildcpu/buildcpu_test.go +++ b/go/buildcpu/buildcpu_test.go @@ -4,77 +4,72 @@ import ( "os" "path/filepath" "reflect" + "runtime" "testing" ) -// The cap's words, a node's share, the unit quota and the threads a step is given, in one table (issue 1806). -func TestCapQuotaAndThreads(t *testing.T) { +// The node's share as a quota, the threads one step is given across every build slot of the node, and the words the +// composer hands, in one table (ADR 0553, issue 1806). +func TestShareQuotaAndThreads(t *testing.T) { for _, c := range []struct { - name, setting, node string - cores, slots int - percent, quota int - threads int - refused bool + name string + percent, cores, slots int + quota, threads int }{ - {name: "default for shanks", setting: Defaults, node: "shanks", cores: 24, slots: 3, percent: 50, quota: 1200, threads: 4}, - {name: "default for ace", setting: Defaults, node: "ace", cores: 24, slots: 2, percent: 75, quota: 1800, threads: 9}, - {name: "default for g14", setting: Defaults, node: "g14", cores: 16, slots: 1, percent: 50, quota: 800, threads: 8}, - {name: "a node not named", setting: Defaults, node: "novox", cores: 8, slots: 1, percent: DefaultPercent, quota: 400, threads: 4}, - {name: "percent sign and spaces", setting: " shanks = 25% ", node: "shanks", cores: 24, slots: 3, percent: 25, quota: 600, threads: 2}, - {name: "one processor at least", setting: "tiny=10", node: "tiny", cores: 2, slots: 4, percent: 10, quota: 100, threads: 1}, - {name: "zero slots counts as one", setting: "x=100", node: "x", cores: 4, slots: 0, percent: 100, quota: 400, threads: 4}, - {name: "zero refused", setting: "shanks=0", node: "shanks", refused: true}, - {name: "over a hundred refused", setting: "shanks=150", node: "shanks", refused: true}, - {name: "no number refused", setting: "shanks", node: "shanks", refused: true}, - {name: "twice refused", setting: "a=1,a=2", node: "a", refused: true}, + {"shanks: half of 24 across 9 slots", 50, 24, 9, 1200, 1}, + {"shanks: half of 24 across 4 slots", 50, 24, 4, 1200, 3}, + {"ace: three quarters of 24 across 6 slots", 75, 24, 6, 1800, 3}, + {"g14: half of 16 across 1 slot", 50, 16, 1, 800, 8}, + {"one processor at least", 10, 2, 4, 100, 1}, + {"no slots counts as one", 100, 4, 0, 400, 4}, + {"a share out of range is the default", 0, 8, 1, 0, 4}, } { - t.Run(c.name, func(t *testing.T) { - p, err := Of(c.setting, c.node) - if c.refused { - if err == nil { - t.Fatalf("Of(%q) = %d, want refused", c.setting, p) - } - return + if c.quota != 0 { + if q := Quota(c.percent, c.cores); q != c.quota { + t.Errorf("%s: Quota = %d, want %d", c.name, q, c.quota) } - if err != nil { - t.Fatal(err) - } - if p != c.percent { - t.Fatalf("percent = %d, want %d", p, c.percent) - } - if q := Quota(p, c.cores); q != c.quota { - t.Errorf("Quota = %d, want %d", q, c.quota) - } - if th := Threads(p, c.cores, c.slots); th != c.threads { - t.Errorf("Threads = %d, want %d", th, c.threads) - } - }) + } + if th := Threads(c.percent, c.cores, c.slots); th != c.threads { + t.Errorf("%s: Threads = %d, want %d", c.name, th, c.threads) + } } - caps, _ := Parse("ace=75,shanks=50%") - if got := Format(caps); got != "ace=75,shanks=50" { - t.Errorf("Format = %q", got) + words := map[string]string{ShareWord: "75", SlotsWord: "6"} + l := FromWords(func(k string) string { return words[k] }, 2) + if l.Percent != 75 || l.From != ShareWord || l.Slots != 6 || l.SlotsFrom != SlotsWord || l.Threads != Threads(75, runtime.NumCPU(), 6) { + t.Errorf("from the words: %+v", l) } - if got := WithEnv([]string{"A=1", "GOMAXPROCS=24"}, 3); !reflect.DeepEqual(got, []string{"A=1", "GOMAXPROCS=3", "UV_THREADPOOL_SIZE=3"}) { - t.Errorf("WithEnv = %q", got) + // Told nothing (or nonsense), a module assumes every build seat beside it at its own capacity, at the default share. + words = map[string]string{ShareWord: "250", SlotsWord: "many"} + if l := FromWords(func(k string) string { return words[k] }, 3); l.Percent != DefaultPercent || l.Slots != 3*BuildSeats || l.From != "default" { + t.Errorf("without usable words: %+v", l) + } + if got := Env(0); !reflect.DeepEqual(got, []string{"GOMAXPROCS=1", "UV_THREADPOOL_SIZE=1"}) { + t.Errorf("Env = %q", got) } } -// What the kernel holds a process to is read from its cgroup and stat files, not assumed. +// What the kernel holds a process to is read from its unit's and its slice's cgroup and its stat file, not assumed. func TestReadInForce(t *testing.T) { dir := t.TempDir() cg := filepath.Join(dir, "cg") - unit := filepath.Join(cg, "system.slice", "mesh-build-go-runtime.service") + slice := filepath.Join(cg, "meshyield.slice") + unit := filepath.Join(slice, "mesh-build-go-runtime.service") if err := os.MkdirAll(unit, 0o755); err != nil { t.Fatal(err) } - for name, v := range map[string]string{"cpu.idle": "1\n", "cpu.weight": "0\n", "cpu.max": "1200000 100000\n", "io.weight": "default 1\n"} { - if err := os.WriteFile(filepath.Join(unit, name), []byte(v), 0o644); err != nil { - t.Fatal(err) + for at, files := range map[string]map[string]string{ + slice: {"cpu.idle": "1\n", "cpu.weight": "0\n", "cpu.max": "1200000 100000\n", "io.weight": "default 1\n"}, + unit: {"cpu.idle": "0\n", "cpu.weight": "100\n", "cpu.max": "max 100000\n", "io.weight": "default 100\n"}, + } { + for name, v := range files { + if err := os.WriteFile(filepath.Join(at, name), []byte(v), 0o644); err != nil { + t.Fatal(err) + } } } self := filepath.Join(dir, "cgroup") stat := filepath.Join(dir, "stat") - _ = os.WriteFile(self, []byte("0::/system.slice/mesh-build-go-runtime.service\n"), 0o644) + _ = os.WriteFile(self, []byte("0::/meshyield.slice/mesh-build-go-runtime.service\n"), 0o644) // A command with a space and a parenthesis in it, then nice 19 in field 19. _ = os.WriteFile(stat, []byte("42 (mesh (build) go) S 1 42 42 0 -1 4194560 1 0 0 0 0 0 0 0 39 19 8 0 1 2 3\n"), 0o644) cgroupRoot, procSelfCgroup, procSelfStat = cg, self, stat @@ -83,12 +78,13 @@ func TestReadInForce(t *testing.T) { }) got := ReadInForce() - want := InForce{Nice: 19, Cgroup: "/system.slice/mesh-build-go-runtime.service", CPUIdle: "1", CPUWeight: "0", - CPUMax: "1200000 100000", Quota: 1200, IOWeight: "default 1"} + want := InForce{Nice: 19, Cgroup: "/meshyield.slice/mesh-build-go-runtime.service", + Unit: Group{Path: "/meshyield.slice/mesh-build-go-runtime.service", CPUIdle: "0", CPUWeight: "100", + CPUMax: "max 100000", IOWeight: "default 100"}, + Slice: Group{Path: "/meshyield.slice", CPUIdle: "1", CPUWeight: "0", CPUMax: "1200000 100000", + IOWeight: "default 1"}, + Quota: 1200} if !reflect.DeepEqual(got, want) { t.Fatalf("ReadInForce = %+v\nwant %+v", got, want) } - if q := quotaOf("max 100000"); q != 0 { - t.Errorf("no quota read as %d", q) - } } diff --git a/go/buildstep/capacity_test.go b/go/buildstep/capacity_test.go index 8f1a7ac..632cdfc 100644 --- a/go/buildstep/capacity_test.go +++ b/go/buildstep/capacity_test.go @@ -37,18 +37,17 @@ func TestNodeCapacity(t *testing.T) { } } -// Issue 1806: a step's limits come from the cap in the same settings file, read at every call; a cap that cannot be -// read still bounds the step, at the default. +// ADR 0553 §4: a step's limits come from the composer's words; without them, every build seat at the module's own +// capacity at the default share. func TestNodeLimits(t *testing.T) { - file := filepath.Join(t.TempDir(), "settings.json") - os.WriteFile(file, []byte(`{"capacity":"shanks=3","cpu-cap":"shanks=25"}`), 0o600) - if l := NodeLimits(file, "shanks", 3, nil); l.Percent != 25 || l.Slots != 3 || l.Threads < 1 { - t.Errorf("from the file: %+v", l) + t.Setenv("MESH_BUILD_CPU_SHARE", "") + t.Setenv("MESH_BUILD_SLOTS", "") + if l := NodeLimits(3); l.Percent != 50 || l.Slots != 9 { + t.Errorf("without words: %+v", l) } - for _, body := range []string{`{"capacity":"shanks=3"}`, `{"cpu-cap":"shanks=0"}`, `not json`} { - os.WriteFile(file, []byte(body), 0o600) - if l := NodeLimits(file, "shanks", 1, nil); l.Percent != 50 { - t.Errorf("%s gives %d%%, want the default 50", body, l.Percent) - } + t.Setenv("MESH_BUILD_CPU_SHARE", "75") + t.Setenv("MESH_BUILD_SLOTS", "5") + if l := NodeLimits(3); l.Percent != 75 || l.Slots != 5 || l.Threads < 1 { + t.Errorf("from the words: %+v", l) } } diff --git a/go/buildstep/cpu.go b/go/buildstep/cpu.go index 754cd3e..6147202 100644 --- a/go/buildstep/cpu.go +++ b/go/buildstep/cpu.go @@ -1,40 +1,15 @@ package buildstep import ( - "encoding/json" "os" "git.novox.be/novox/mesh-sdk/go/buildcpu" ) -// NodeLimits is what one step on node is held to (novox/hq issue 1806): the node's processor cap from the module's -// settings file at path (buildcpu.Setting, its default when the file does not set it), the machine's processors, and -// the node's capacity, so the steps that run at once start no more threads together than the cap gives. Read at every -// call, like the capacity, so a change takes effect at the next step. A file or a setting that cannot be read gives the -// default cap and says why: a step still runs with a bound, never without one. -func NodeLimits(path, node string, slots int, logf func(string, ...any)) buildcpu.Limits { - setting := buildcpu.Defaults - if path != "" { - if raw, err := os.ReadFile(path); err != nil { - sayTo(logf, "the processor cap cannot be read, so %s builds under the default cap: %v", node, err) - } else { - var s map[string]any - if err := json.Unmarshal(raw, &s); err != nil { - sayTo(logf, "the settings file %s is not JSON, so %s builds under the default cap: %v", path, node, err) - } else if v, ok := s[buildcpu.Setting].(string); ok { - setting = v - } - } - } - l, err := buildcpu.LimitsFor(setting, node, slots) - if err != nil { - sayTo(logf, "%v, so %s builds under the default cap of %d%%", err, node, buildcpu.DefaultPercent) - } - return l -} - -func sayTo(logf func(string, ...any), format string, args ...any) { - if logf != nil { - logf(format, args...) - } +// NodeLimits is what one step of a build module is held to (novox/hq ADR 0553 §4): the node's processor share and every +// build slot of the node, from the words the composer gives the module (buildcpu.ShareWord, buildcpu.SlotsWord), and the +// machine's processors. A module told neither assumes every build seat beside it at its own capacity, own, so its steps +// stay within the default share with the others'. +func NodeLimits(own int) buildcpu.Limits { + return buildcpu.FromWords(os.Getenv, own) } diff --git a/go/catalogue/holdings_test.go b/go/catalogue/holdings_test.go index c8a15b5..dedc566 100644 --- a/go/catalogue/holdings_test.go +++ b/go/catalogue/holdings_test.go @@ -172,7 +172,7 @@ func TestAStoreRowWithoutAProtocolKeepsTheCompiledOne(t *testing.T) { t.Cleanup(func() { UseSeats(was) }) UseSeats([]Seat{{Name: "node-build-go", Scope: ScopeNode, Decision: "row"}}) got, ok := SeatNamed("node-build-go") - if !ok || len(got.Accepts) == 0 || !got.PulledByKind { + if !ok || len(got.Accepts) == 0 || !got.PulledByKind || !got.Yields { t.Fatalf("the Go build seat lost what it accepts when loaded from the store: %+v", got) } if got.Decision != "row" { diff --git a/go/catalogue/runtime.go b/go/catalogue/runtime.go index 7aa9e36..b0139c8 100644 --- a/go/catalogue/runtime.go +++ b/go/catalogue/runtime.go @@ -329,14 +329,6 @@ func (r Resolution) ownRuntimes(with Rendering) ([]map[string]any, error) { process[HealthField] = m.RuntimeHealth healthInto(process, m, with) } - // A build seat's holder gives way to everything else on its node (novox/hq issue 1806). - yields, err := r.yieldsOf(m, with) - if err != nil { - return nil, err - } - if yields != nil { - process["yields"] = yields - } if err := artifactsInto(process, RuntimeModule, with); err != nil { return nil, err } diff --git a/go/catalogue/runtime_test.go b/go/catalogue/runtime_test.go index 40f6526..16c02b4 100644 --- a/go/catalogue/runtime_test.go +++ b/go/catalogue/runtime_test.go @@ -498,34 +498,6 @@ func TestAModuleOfItsOwnAccountIsServedByARuntimeOfItsOwn(t *testing.T) { if _, told := env[RuntimeOperatorAccount]; told { t.Error("a runtime of a module's own account is told the operator's account") } - if _, yields := own["yields"]; yields { - t.Errorf("telegram holds no build seat and yields: %v", own["yields"]) - } - // A build seat's holder yields: idle priority, under this node's share of its cpu-cap, the default where no layer - // sets one (issue 1806). - builder := telegram - builder.Claims = []Claim{{Name: "node-build-go"}} - for _, c := range []struct { - layers []Layer - share int - }{ - {nil, 50}, - {[]Layer{{From: "anchor", Values: map[string]any{"cpu-cap": "anchor=30,other=90"}}}, 30}, - } { - with.Settings = SettingsBy{"telegram": c.layers} - runtimes, err := Resolution{Node: "anchor", Modules: []Manifest{builder, goRuntime}}.ownRuntimes(with) - if err != nil { - t.Fatal(err) - } - if got := fmt.Sprint(runtimes[0]["yields"]); got != fmt.Sprintf("map[cpu-share:%d priority:idle]", c.share) { - t.Errorf("a build seat's holder under %v yields %s", c.layers, got) - } - } - with.Settings = SettingsBy{"telegram": {{From: "anchor", Values: map[string]any{"cpu-cap": "anchor=0"}}}} - if _, err := (Resolution{Node: "anchor", Modules: []Manifest{builder, goRuntime}}).ownRuntimes(with); err == nil { - t.Error("a cap of 0 percent was composed") - } - with.Settings = nil // Without the machine's runtime to run it from, it is refused in words. if _, err := (Resolution{Node: "anchor", Modules: []Manifest{telegram}}).ownRuntimes(with); err == nil { t.Error("a module of its own account composed without a runtime program") diff --git a/go/catalogue/seats.go b/go/catalogue/seats.go index bc43fe1..805d0be 100644 --- a/go/catalogue/seats.go +++ b/go/catalogue/seats.go @@ -49,10 +49,10 @@ type Seat struct { // order Accepts lists them (novox/hq ADR 0525 §2, ADR 0536 §4): the build seats'. Compiled, never stored, like // Receives. PulledByKind bool - // Yields says the seat's holder gives way to everything else on its node (novox/hq issue 1806): its runtime runs at - // the lowest CPU and IO priority and under its node's processor cap, the holder's setting `cpu-cap` - // (buildcpu.Setting). The build seats': a build must never slow the operator's desktop. Compiled, never stored, like - // Receives. + // Yields says the seat's holder gives way to everything else on its node (novox/hq ADR 0553): its runtime runs at + // idle priority in the node's one yielding slice, under the node's one processor share (buildcpu.ShareSetting) that + // every yielding holder of the node shares. The build seats': a build must never slow the operator's desktop. + // Compiled, never stored, like Receives. Yields bool // Serves carries each verb in full — name, description, schema — because a role's tools are the // mesh's to define and an agent's to call (novox/hq ADR 0132, design 33 §2). @@ -261,11 +261,11 @@ var defaultSeats = append([]Seat{ // its holder taking nothing, kept on the module's own pause key (issue 1887's design limit 2). They replace // node-build-agent, retired with build-agent (ADR 0524 §5). {Name: "node-build-go", Scope: ScopeNode, Accepts: buildAskKinds(), PulledByKind: true, Serves: buildSeatVerbs("Go"), - Yields: true, Decision: "novox/hq ADR 0525, ADR 0536"}, + Yields: true, Decision: "novox/hq ADR 0525, ADR 0536, ADR 0553"}, {Name: "node-build-node", Scope: ScopeNode, Accepts: buildAskKinds(), PulledByKind: true, Serves: buildSeatVerbs("Node"), - Yields: true, Decision: "novox/hq ADR 0525, ADR 0536"}, + Yields: true, Decision: "novox/hq ADR 0525, ADR 0536, ADR 0553"}, {Name: "node-build-image", Scope: ScopeNode, Accepts: buildAskKinds(), PulledByKind: true, Serves: buildSeatVerbs("image"), - Yields: true, Decision: "novox/hq ADR 0525, ADR 0536"}, + Yields: true, Decision: "novox/hq ADR 0525, ADR 0536, ADR 0553"}, // **The mesh's resolvers** (novox/hq ADR 0194, 0196, 0223): every node's internal domain, and // every node and container asks them and nothing else. Replicated since ADR 0223: held on more // than one machine, each answering the same names from the same roster, and every machine's @@ -502,6 +502,7 @@ func UseSeats(s []Seat) { row.Paths = d.Paths row.Replicated = d.Replicated row.PulledByKind = d.PulledByKind + row.Yields = d.Yields // never stored (ADR 0553) row.Serves = optionalAsCompiled(row.Serves, d.Serves) } merged = append(merged, row) diff --git a/go/catalogue/seats_test.go b/go/catalogue/seats_test.go index caa5a25..4e65fca 100644 --- a/go/catalogue/seats_test.go +++ b/go/catalogue/seats_test.go @@ -4,6 +4,8 @@ import ( "regexp" "strings" "testing" + + "git.novox.be/novox/mesh-sdk/go/buildcpu" ) // Defends novox/hq ADR 0110: a seat is a module assignment from a closed set. @@ -324,6 +326,9 @@ func TestNodeBuildAgentIsRetiredForTheBuildSeats(t *testing.T) { if !ok || s.Scope != ScopeNode || !s.PulledByKind || strings.Join(s.Accepts, ",") != "delivery,check,recheck" { t.Fatalf("%s = %+v", name, s) } + if !s.Yields { + t.Errorf("%s does not yield (ADR 0553)", name) + } var verbs []string for _, v := range s.Serves { verbs = append(verbs, v.Name) @@ -332,4 +337,14 @@ func TestNodeBuildAgentIsRetiredForTheBuildSeats(t *testing.T) { t.Errorf("%s serves %v", name, verbs) } } + // The build seats are the seats that yield, as many as a step told nothing assumes beside it (ADR 0553 §4). + yielding := 0 + for _, s := range Seats() { + if s.Yields { + yielding++ + } + } + if yielding != buildcpu.BuildSeats { + t.Errorf("%d seats yield, and buildcpu.BuildSeats says %d", yielding, buildcpu.BuildSeats) + } } diff --git a/go/catalogue/yields.go b/go/catalogue/yields.go deleted file mode 100644 index e0d0034..0000000 --- a/go/catalogue/yields.go +++ /dev/null @@ -1,41 +0,0 @@ -package catalogue - -import ( - "fmt" - - "git.novox.be/novox/mesh-sdk/go/buildcpu" -) - -// yieldsOf is how the runtime of its own a module is served by gives way on this node (novox/hq issue 1806), or nil -// when it does not: a module holding a seat that yields (Seat.Yields, the build seats) runs at idle priority and under -// this node's share of its setting `cpu-cap` (buildcpu.Setting), its default when no layer sets it. -// -// In the node-engine's words (declaration.Yields), which it writes into the unit: the kernel holds the bound, not the -// module. -func (r Resolution) yieldsOf(m Manifest, with Rendering) (map[string]any, error) { - yields := false - for _, c := range m.Claims { - if s, ok := SeatNamed(c.Name); ok && s.Yields { - yields = true - } - } - if !yields { - return nil, nil - } - setting := buildcpu.Defaults - for _, s := range Effective(m, with.Settings[m.Module]) { - if s.Key == buildcpu.Setting { - v, ok := s.Value.(string) - if !ok { - return nil, fmt.Errorf("%s's %s is %v, not = pairs (novox/hq issue 1806)", - m.Module, buildcpu.Setting, s.Value) - } - setting = v - } - } - share, err := buildcpu.Of(setting, r.Node) - if err != nil { - return nil, fmt.Errorf("%s's %s: %w (novox/hq issue 1806)", m.Module, buildcpu.Setting, err) - } - return map[string]any{"priority": "idle", "cpu-share": share}, nil -} diff --git a/go/declaration/declaration.go b/go/declaration/declaration.go index 314cd58..3d70e00 100644 --- a/go/declaration/declaration.go +++ b/go/declaration/declaration.go @@ -917,22 +917,30 @@ type Process struct { // timing, judged by the node-engine beside liveness. Absent: judged alive or not, and nothing more. Health *Health `json:"health,omitempty"` - // Yields says this process gives way to everything else on its machine (novox/hq issue 1806): the - // runtime of a build seat's holder, whose builds must never slow the operator's desktop. Absent: the - // machine's defaults. For a process that stays up. + // Yields says this process gives way to everything else on its machine (novox/hq ADR 0553, issue 1806): the + // runtime of a build seat's holder, whose builds must never slow the operator's desktop. Absent: the machine's + // defaults. For a process that stays up. Yields *Yields `json:"yields,omitempty"` } -// YieldIdle is the one priority a process yields at: the lowest CPU and IO priority there is. +// YieldIdle is the one priority a process yields at: the lowest there is. const YieldIdle = "idle" -// Yields is how a process gives way, written into its unit by the node-engine (novox/hq issue 1806). +// YieldSlice is the one slice the node-engine places every yielding process of its node in (novox/hq ADR 0553 §2): a +// slice at the top of the hierarchy, beside the operator's user slice and the system's, so its idle weight and its +// quota bind against everything else on the machine. No dash in its name: a dash makes a slice a child of the slice +// named before it, where its weight would count only against its siblings. +const YieldSlice = "meshyield.slice" + +// Yields is how a process gives way, written by the node-engine (novox/hq ADR 0553). // -// **Priority** "idle": CPUWeight=idle (its cgroup runs only on cycles nothing else wants), IOWeight=1, -// Nice=19 for every process it starts, and the best-effort IO class at its lowest level (never the idle IO -// class, which a busy disk starves for good). **CPUShare** is the most of the machine's processors it may -// take, in percent: the node-engine writes CPUQuota for the processors the machine has, so the bound is -// the kernel's. 0 is no cap. +// **Priority** "idle": the process runs in YieldSlice, whose CPUWeight is idle (it runs only on cycles nothing else +// wants) and whose IOWeight is 1, with Nice=19 and the lowest best-effort IO level for every process it starts. The IO +// controls bind only where the disk's scheduler honours them (bfq, or io.cost for the weight); under `none`, the +// usual one for NVMe, they do nothing, and the CPU bound is what holds. **CPUShare** is the most of the machine's +// processors the slice may take, in percent, shared by every yielding process of the node together: the node-engine +// writes it as the slice's CPUQuota for the processors the machine has, so the bound is the kernel's. Every yielding +// process of one node carries the same share: the composer gives the node's one value (ADR 0553 §3). 0 is no cap. type Yields struct { Priority string `json:"priority,omitempty"` CPUShare int `json:"cpu-share,omitempty"`