Merge pull request #6442 from Agoric/6433-preload-fewer-vats

fix(swingset): only preload maxVatsOnline/2 vats

packages/SwingSet/src/kernel/vat-warehouse.js

@@ -1,3 +1,4 @@
+/* eslint-disable no-await-in-loop,@jessie.js/no-nested-await */
 // @ts-check
 import { assert, details as X, quote as q } from '@agoric/assert';
 import { isNat } from '@agoric/nat';
@@ -162,21 +163,33 @@ export function makeVatWarehouse(kernelKeeper, vatLoader, policyOptions) {
   /** @param {typeof console.log} logStartup */
   async function start(logStartup) {
     const recreate = true; // note: PANIC on failure to recreate
+    const maxPreload = maxVatsOnline / 2;
+    let numPreloaded = 0;
 
     // NOTE: OPTIMIZATION OPPORTUNITY: replay vats in parallel
 
-    // instantiate all static vats
+    // instantiate all static vats, in lexicographic order, up to the
+    // maxPreload limit
     for (const [name, vatID] of kernelKeeper.getStaticVats()) {
+      if (numPreloaded >= maxPreload) {
+        break;
+      }
       logStartup(`provideVatKeeper for vat ${name} as vat ${vatID}`);
       // eslint-disable-next-line no-await-in-loop
       await ensureVatOnline(vatID, recreate);
+      numPreloaded += 1;
     }
 
-    // instantiate all dynamic vats
+    // then instantiate all dynamic vats, in creation order, also
+    // subject to maxPreload
     for (const vatID of kernelKeeper.getDynamicVats()) {
+      if (numPreloaded >= maxPreload) {
+        break;
+      }
       logStartup(`provideVatKeeper for dynamic vat ${vatID}`);
       // eslint-disable-next-line no-await-in-loop
       await ensureVatOnline(vatID, recreate);
+      numPreloaded += 1;
     }
   }
 

packages/SwingSet/test/vat-warehouse/test-preload.js

@@ -0,0 +1,126 @@
+// eslint-disable-next-line import/order
+import { test } from '../../tools/prepare-test-env-ava.js';
+
+// import * as proc from 'child_process';
+import tmp from 'tmp';
+import { makeSnapStore, makeSnapStoreIO } from '@agoric/swing-store';
+import { provideHostStorage } from '../../src/controller/hostStorage.js';
+import { initializeSwingset, makeSwingsetController } from '../../src/index.js';
+
+test('only preload maxVatsOnline vats', async t => {
+  const bpath = new URL('vat-preload-bootstrap.js', import.meta.url).pathname;
+  const tpath = new URL('vat-preload-extra.js', import.meta.url).pathname;
+  // this combination of config and initOpts means we have only two
+  // initial vats: v1-bootstrap and v2-vatAdmin
+  const config = {
+    defaultManagerType: 'xs-worker',
+    defaultReapInterval: 'never',
+    bootstrap: 'bootstrap',
+    vats: {
+      bootstrap: {
+        sourceSpec: bpath,
+      },
+    },
+    bundles: { extra: { sourceSpec: tpath } },
+  };
+  const initOpts = {
+    addComms: false,
+    addVattp: false,
+    addTimer: false,
+  };
+  const argv = [];
+
+  const snapstorePath = tmp.dirSync({ unsafeCleanup: true }).name;
+  const snapStore = makeSnapStore(snapstorePath, makeSnapStoreIO());
+  const hostStorage = { snapStore, ...provideHostStorage() };
+
+  await initializeSwingset(config, argv, hostStorage, initOpts);
+
+  /* we use vat-warehouse's built-in instrumentation, but I'll leave
+   * this alternative here in case it's ever useful
+  // this lets us snoop on which workers are still alive
+  const workers = new Map();
+  function spawn(...args) {
+    const worker = proc.spawn(...args);
+    const name = args[1][0]; // e.g. 'v1:bootstrap'
+    workers.set(name, worker);
+    return worker;
+  }
+  const isAlive = name =>
+    workers.has(name) && workers.get(name).exitCode === null;
+  */
+
+  // we'll create a 'canary' vat, and ten extras
+  const all = ['bootstrap', 'vatAdmin', 'canary'];
+  for (let count = 0; count < 10; count += 1) {
+    all.push(`extra-${count}`);
+  }
+
+  function areLiving(c, ...expected) {
+    expected = new Set(expected);
+    const living = c.getStatus().activeVats.map(info => info.options.name);
+    for (const name of all) {
+      t.is(living.indexOf(name) !== -1, expected.has(name), name);
+    }
+  }
+
+  const maxVatsOnline = 10;
+  const warehousePolicy = { maxVatsOnline };
+  const runtimeOptions = { warehousePolicy /* , spawn */ };
+
+  const c1 = await makeSwingsetController(hostStorage, null, runtimeOptions);
+  c1.pinVatRoot('bootstrap');
+  await c1.run();
+  areLiving(c1, 'bootstrap', 'vatAdmin');
+
+  // launch v3-canary
+  c1.queueToVatRoot('bootstrap', 'launchCanary', []);
+  await c1.run();
+  areLiving(c1, 'bootstrap', 'vatAdmin', 'canary');
+
+  // then launch v4-extra-0 through v13-extra-9, which knocks the
+  // v3-canary and v4/v5 workers offline
+  c1.queueToVatRoot('bootstrap', 'launchExtra', []);
+  await c1.run();
+  areLiving(
+    c1,
+    'bootstrap',
+    'vatAdmin',
+    // 'canary', -- evicted
+    // 'extra-0', -- evicted
+    // 'extra-1', -- evicted
+    'extra-2',
+    'extra-3',
+    'extra-4',
+    'extra-5',
+    'extra-6',
+    'extra-7',
+    'extra-8',
+    'extra-9',
+  );
+
+  // shut down that controller, then start a new one
+  await c1.shutdown();
+  const c2 = await makeSwingsetController(hostStorage, null, runtimeOptions);
+
+  // we only preload maxVatsOnline/2 vats: the static vats in
+  // lexicographic order (e.g. 1,10,11,2,3,4, except here we only have
+  // v1 and v2 as static vats), and the dynamic vats in creation order
+  areLiving(c2, 'bootstrap', 'vatAdmin', 'canary', 'extra-0', 'extra-1');
+
+  // send a message to an offline extra vat, assert it came online
+  c2.queueToVatRoot('bootstrap', 'ping', ['extra-6']);
+  await c2.run();
+
+  areLiving(
+    c2,
+    'bootstrap',
+    'vatAdmin',
+    'canary',
+    'extra-0',
+    'extra-1',
+    'extra-6', // now online
+  );
+
+  await c2.shutdown();
+});

packages/SwingSet/test/vat-warehouse/test-warehouse.js

@@ -10,16 +10,26 @@ import { test } from '../../tools/prepare-test-env-ava.js';
 import fs from 'fs';
 import tmp from 'tmp';
 import { initSwingStore } from '@agoric/swing-store';
-import { loadBasedir, buildVatController } from '../../src/index.js';
+import { buildVatController } from '../../src/index.js';
 import { makeLRU } from '../../src/kernel/vat-warehouse.js';
 
 async function makeController(managerType, runtimeOptions, snapshotInterval) {
-  const config = await loadBasedir(new URL('./', import.meta.url).pathname);
-  if (snapshotInterval) {
-    config.snapshotInterval = snapshotInterval;
-  }
-  assert(config.vats);
-  config.vats.target.creationOptions = { managerType, enableDisavow: true };
+  const bpath = new URL('bootstrap.js', import.meta.url).pathname;
+  const tpath = new URL('vat-target.js', import.meta.url).pathname;
+  const config = {
+    snapshotInterval,
+    bootstrap: 'bootstrap',
+    vats: {
+      bootstrap: {
+        sourceSpec: bpath,
+      },
+      target: {
+        creationOptions: { managerType },
+        sourceSpec: tpath,
+      },
+    },
+  };
+
   config.vats.target2 = config.vats.target;
   config.vats.target3 = config.vats.target;
   config.vats.target4 = config.vats.target;

packages/SwingSet/test/vat-warehouse/vat-preload-bootstrap.js

@@ -0,0 +1,42 @@
+/* eslint-disable no-await-in-loop */
+import { E } from '@endo/eventual-send';
+import { Far } from '@endo/marshal';
+
+export function buildRootObject() {
+  const extras = new Map(); // count -> root
+  let vatAdminSvc;
+  let bcap;
+
+  async function start(name) {
+    const opts = { name, vatParameters: { name } };
+    const { root } = await E(vatAdminSvc).createVat(bcap, opts);
+    return root;
+  }
+
+  return Far('root', {
+    async bootstrap(vats, devices) {
+      vatAdminSvc = await E(vats.vatAdmin).createVatAdminService(
+        devices.vatAdmin,
+      );
+      bcap = await E(vatAdminSvc).getNamedBundleCap('extra');
+    },
+
+    async launchCanary() {
+      const canary = await start('canary');
+      extras.set('canary', canary);
+    },
+
+    async launchExtra() {
+      for (let count = 0; count < 10; count += 1) {
+        const name = `extra-${count}`;
+        const root = await start(name);
+        extras.set(name, root);
+      }
+    },
+
+    ping(which) {
+      console.log(`ping ${which}`);
+      return E(extras.get(which)).ping();
+    },
+  });
+}

packages/SwingSet/test/vat-warehouse/vat-preload-extra.js

@@ -0,0 +1,8 @@
+import { Far } from '@endo/marshal';
+
+export function buildRootObject(_vatPowers, _vatParameters) {
+  // console.log(`extra: ${vatParameters.name}`);
+  return Far('root', {
+    ping() {},
+  });
+}