fix(swingset): use "dirt" to schedule vat reap/bringOutYourDead

packages/SwingSet/src/controller/initializeKernel.js

@@ -9,14 +9,32 @@ import { insistVatID } from '../lib/id.js';
 import { makeVatSlot } from '../lib/parseVatSlots.js';
 import { insistStorageAPI } from '../lib/storageAPI.js';
 import { makeVatOptionRecorder } from '../lib/recordVatOptions.js';
-import makeKernelKeeper from '../kernel/state/kernelKeeper.js';
+import makeKernelKeeper, {
+  DEFAULT_DELIVERIES_PER_BOYD,
+  DEFAULT_GC_KREFS_PER_BOYD,
+} from '../kernel/state/kernelKeeper.js';
 import { exportRootObject } from '../kernel/kernel.js';
 import { makeKernelQueueHandler } from '../kernel/kernelQueue.js';
 
+/**
+ * @typedef { import('../types-external.js').SwingSetKernelConfig } SwingSetKernelConfig
+ * @typedef { import('../types-external.js').SwingStoreKernelStorage } SwingStoreKernelStorage
+ * @typedef { import('../types-internal.js').InternalKernelOptions } InternalKernelOptions
+ * @typedef { import('../types-internal.js').ReapDirtThreshold } ReapDirtThreshold
+ */
+
 function makeVatRootObjectSlot() {
   return makeVatSlot('object', true, 0);
 }
 
+/**
+ * @param {SwingSetKernelConfig} config
+ * @param {SwingStoreKernelStorage} kernelStorage
+ * @param {*} [options]
+ * @returns {Promise<string | undefined>} KPID of the bootstrap message
+ *                                        result promise
+ */
+
 export async function initializeKernel(config, kernelStorage, options = {}) {
   const {
     verbose = false,
@@ -25,22 +43,27 @@ export async function initializeKernel(config, kernelStorage, options = {}) {
   const logStartup = verbose ? console.debug : () => 0;
   insistStorageAPI(kernelStorage.kvStore);
 
-  const kernelSlog = null;
-  const kernelKeeper = makeKernelKeeper(kernelStorage, kernelSlog);
+  const kernelKeeper = makeKernelKeeper(kernelStorage, 'uninitialized');
   const optionRecorder = makeVatOptionRecorder(kernelKeeper, bundleHandler);
 
-  const wasInitialized = kernelKeeper.getInitialized();
-  assert(!wasInitialized);
   const {
     defaultManagerType,
-    defaultReapInterval,
+    defaultReapInterval = DEFAULT_DELIVERIES_PER_BOYD,
+    defaultReapGCKrefs = DEFAULT_GC_KREFS_PER_BOYD,
     relaxDurabilityRules,
     snapshotInitial,
     snapshotInterval,
   } = config;
+  /** @type { ReapDirtThreshold } */
+  const defaultReapDirtThreshold = {
+    deliveries: defaultReapInterval,
+    gcKrefs: defaultReapGCKrefs,
+    computrons: 'never', // TODO no knob?
+  };
+  /** @type { InternalKernelOptions } */
   const kernelOptions = {
     defaultManagerType,
-    defaultReapInterval,
+    defaultReapDirtThreshold,
     relaxDurabilityRules,
     snapshotInitial,
     snapshotInterval,
@@ -49,7 +72,7 @@ export async function initializeKernel(config, kernelStorage, options = {}) {
 
   for (const id of Object.keys(config.idToBundle || {})) {
     const bundle = config.idToBundle[id];
-    assert.equal(bundle.moduleFormat, 'endoZipBase64');
+    assert(bundle.moduleFormat === 'endoZipBase64');
     if (!kernelKeeper.hasBundle(id)) {
       kernelKeeper.addBundle(id, bundle);
     }
@@ -64,7 +87,7 @@ export async function initializeKernel(config, kernelStorage, options = {}) {
 
   // generate the genesis vats
   await null;
-  if (config.vats) {
+  if (config.vats && Object.keys(config.vats).length) {
     for (const name of Object.keys(config.vats)) {
       const {
         bundleID,
@@ -86,6 +109,8 @@ export async function initializeKernel(config, kernelStorage, options = {}) {
         'useTranscript',
         'critical',
         'reapInterval',
+        'reapGCKrefs',
+        'neverReap',
         'nodeOptions',
       ]);
       const vatID = kernelKeeper.allocateVatIDForNameIfNeeded(name);

packages/SwingSet/src/controller/initializeSwingset.js

@@ -256,7 +256,10 @@ export async function loadSwingsetConfigFile(configPath) {
 }
 
 export function swingsetIsInitialized(kernelStorage) {
-  return !!kernelStorage.kvStore.get('initialized');
+  return !!(
+    kernelStorage.kvStore.get('version') ||
+    kernelStorage.kvStore.get('initialized')
+  );
 }
 
 /**
@@ -397,7 +400,7 @@ export async function initializeSwingset(
         enableSetup: true,
         managerType: 'local',
         useTranscript: false,
-        reapInterval: 'never',
+        neverReap: true,
       },
     };
   }

packages/SwingSet/src/controller/upgradeSwingset.js

@@ -0,0 +1,204 @@
+import {
+  DEFAULT_REAP_DIRT_THRESHOLD_KEY,
+  DEFAULT_GC_KREFS_PER_BOYD,
+  getAllDynamicVats,
+  getAllStaticVats,
+} from '../kernel/state/kernelKeeper.js';
+
+const upgradeVatV0toV1 = (kvStore, defaultReapDirtThreshold, vatID) => {
+  // This is called, once per vat, when upgradeSwingset migrates from
+  // v0 to v1
+
+  // schema v0:
+  // Each vat has a `vNN.reapInterval` and `vNN.reapCountdown`.
+  // vNN.options has a `.reapInterval` property (however it was not
+  // updated by processChangeVatOptions).  Either all are numbers, or
+  // all are 'never'.
+
+  const oldReapIntervalKey = `${vatID}.reapInterval`;
+  const oldReapCountdownKey = `${vatID}.reapCountdown`;
+  const vatOptionsKey = `${vatID}.options`;
+
+  // schema v1:
+  // Each vat has a `vNN.reapDirt`, and vNN.options has a
+  // `.reapDirtThreshold` property (which overrides kernel-wide
+  // `defaultReapDirtThreshold`)
+
+  const reapDirtKey = `${vatID}.reapDirt`;
+
+  assert(kvStore.has(oldReapIntervalKey), oldReapIntervalKey);
+  assert(kvStore.has(oldReapCountdownKey), oldReapCountdownKey);
+  assert(!kvStore.has(reapDirtKey), reapDirtKey);
+
+  const reapIntervalString = kvStore.get(oldReapIntervalKey);
+  const reapCountdownString = kvStore.get(oldReapCountdownKey);
+  assert(reapIntervalString !== undefined);
+  assert(reapCountdownString !== undefined);
+
+  const intervalIsNever = reapIntervalString === 'never';
+  const countdownIsNever = reapCountdownString === 'never';
+  // these were supposed to be the same
+  assert(
+    intervalIsNever === countdownIsNever,
+    `reapInterval=${reapIntervalString}, reapCountdown=${reapCountdownString}`,
+  );
+
+  // initialize or upgrade state
+  const reapDirt = {}; // all missing keys are treated as zero
+  const threshold = {};
+
+  if (intervalIsNever) {
+    // old vats that were never reaped (eg comms) used
+    // reapInterval='never', so respect that and set the other
+    // threshold values to never as well
+    threshold.never = true;
+  } else {
+    // deduce delivery count from old countdown values
+    const reapInterval = Number.parseInt(reapIntervalString, 10);
+    const reapCountdown = Number.parseInt(reapCountdownString, 10);
+    const deliveries = reapInterval - reapCountdown;
+    reapDirt.deliveries = Math.max(deliveries, 0); // just in case
+    if (reapInterval !== defaultReapDirtThreshold.deliveries) {
+      threshold.deliveries = reapInterval;
+    }
+  }
+
+  kvStore.delete(oldReapIntervalKey);
+  kvStore.delete(oldReapCountdownKey);
+  kvStore.set(reapDirtKey, JSON.stringify(reapDirt));
+
+  // Update options to use the new schema.
+  const options = JSON.parse(kvStore.get(vatOptionsKey));
+  delete options.reapInterval;
+  options.reapDirtThreshold = threshold;
+  kvStore.set(vatOptionsKey, JSON.stringify(options));
+};
+
+/**
+ * (maybe) upgrade the kernel state to the current schema
+ *
+ * This function is responsible for bringing the kernel's portion of
+ * swing-store (kernelStorage) up to the current version. The host app
+ * must call this each time it launches with a new version of
+ * swingset, before using makeSwingsetController() to build the
+ * kernel/controller (which will throw an error if handed an old
+ * database). It is ok to call it only on those reboots, but it is
+ * also safe to call on every reboot, because upgradeSwingset() is a
+ * no-op if the DB is already up-to-date.
+ *
+ * If an upgrade is needed, this function will modify the DB state, so
+ * the host app must be prepared for export-data callbacks being
+ * called during the upgrade, and it is responsible for doing a
+ * `hostStorage.commit()` afterwards.
+ *
+ * @param {SwingStoreKernelStorage} kernelStorage
+ * @returns {boolean} true if any changes were made
+ */
+export const upgradeSwingset = kernelStorage => {
+  const { kvStore } = kernelStorage;
+  let modified = false;
+  let vstring = kvStore.get('version');
+  if (vstring === undefined) {
+    vstring = '0';
+  }
+  let version = Number(vstring);
+
+  /**
+   * @param {string} key
+   * @returns {string}
+   */
+  function getRequired(key) {
+    if (!kvStore.has(key)) {
+      throw Error(`storage lacks required key ${key}`);
+    }
+    // @ts-expect-error already checked .has()
+    return kvStore.get(key);
+  }
+
+  // kernelKeeper.js has a large comment that defines our current
+  // kvStore schema, with a section describing the deltas. The upgrade
+  // steps applied here must match.
+
+  // schema v0:
+  //
+  // The kernel overall has `kernel.defaultReapInterval` and
+  // `kernel.initialized = 'true'`.
+  //
+  // Each vat has a `vNN.reapInterval` and `vNN.reapCountdown`.
+  // vNN.options has a `.reapInterval` property (however it was not
+  // updated by processChangeVatOptions, so do not rely upon its
+  // value).  Either all are numbers, or all are 'never'.
+
+  if (version < 1) {
+    // schema v1:
+    //
+    // The kernel overall has `kernel.defaultReapDirtThreshold` and
+    // `kernel.version = '1'` (instead of .initialized).
+    //
+    // Each vat has a `vNN.reapDirt`, and vNN.options has a
+    // `.reapDirtThreshold` property
+
+    // So:
+    // * replace `kernel.initialized` with `kernel.version`
+    // * replace `kernel.defaultReapInterval` with
+    //   `kernel.defaultReapDirtThreshold`
+    // * replace vat's `vNN.reapInterval`/`vNN.reapCountdown` with
+    //   `vNN.reapDirt` and a `vNN.reapDirtThreshold` in `vNN.options`
+    // * then do per-vat upgrades with upgradeVatV0toV1
+
+    assert(kvStore.has('initialized'));
+    kvStore.delete('initialized');
+    // 'version' will be set at the end
+
+    // upgrade from old kernel.defaultReapInterval
+
+    const oldDefaultReapIntervalKey = 'kernel.defaultReapInterval';
+    assert(kvStore.has(oldDefaultReapIntervalKey));
+    assert(!kvStore.has(DEFAULT_REAP_DIRT_THRESHOLD_KEY));
+
+    /**
+     * @typedef { import('../types-internal.js').ReapDirtThreshold } ReapDirtThreshold
+     */
+
+    /** @type ReapDirtThreshold */
+    const threshold = {
+      deliveries: 'never',
+      gcKrefs: 'never',
+      computrons: 'never',
+    };
+
+    const oldValue = getRequired(oldDefaultReapIntervalKey);
+    if (oldValue !== 'never') {
+      const value = Number.parseInt(oldValue, 10);
+      assert.typeof(value, 'number');
+      threshold.deliveries = value;
+      // if BOYD wasn't turned off entirely (eg
+      // defaultReapInterval='never', which only happens in unit
+      // tests), then pretend we wanted a gcKrefs= threshold all
+      // along, so all vats get a retroactive gcKrefs threshold, which
+      // we need for the upcoming slow-vat-deletion to not trigger
+      // gigantic BOYD and break the kernel
+      threshold.gcKrefs = DEFAULT_GC_KREFS_PER_BOYD;
+    }
+    harden(threshold);
+    kvStore.set(DEFAULT_REAP_DIRT_THRESHOLD_KEY, JSON.stringify(threshold));
+    kvStore.delete(oldDefaultReapIntervalKey);
+
+    // now upgrade all vats
+    for (const [_name, vatID] of getAllStaticVats(kvStore)) {
+      upgradeVatV0toV1(kvStore, threshold, vatID);
+    }
+    for (const vatID of getAllDynamicVats(getRequired)) {
+      upgradeVatV0toV1(kvStore, threshold, vatID);
+    }
+
+    modified = true;
+    version = 1;
+  }
+
+  if (modified) {
+    kvStore.set('version', `${version}`);
+  }
+  return modified;
+};
+harden(upgradeSwingset);

packages/SwingSet/src/index.js

@@ -9,7 +9,7 @@ export {
   loadBasedir,
   loadSwingsetConfigFile,
 } from './controller/initializeSwingset.js';
-
+export { upgradeSwingset } from './controller/upgradeSwingset.js';
 export {
   buildMailboxStateMap,
   buildMailbox,