fix https://github.com/uBlockOrigin/uBlock-issues/issues/328

src/js/cachestorage.js

@@ -40,19 +40,28 @@
 
 µBlock.cacheStorage = (function() {
 
-    // Firefox-specific: we use indexedDB because chrome.storage.local() has
+    const STORAGE_NAME = 'uBlock0CacheStorage';
-    // poor performance in Firefox. See:
+
     // https://bugzilla.mozilla.org/show_bug.cgi?id=1371255
-    if ( vAPI.webextFlavor.soup.has('firefox') === false ) {
+    //   Firefox-specific: we use indexedDB because chrome.storage.local() has
+    //   poor performance in Firefox.
+    // https://github.com/uBlockOrigin/uBlock-issues/issues/328
+    //   Use IndexedDB for Chromium as well, to take advantage of LZ4
+    //   compression.
+    if (
+        vAPI.webextFlavor.soup.has('firefox') === false &&
+        vAPI.webextFlavor.soup.has('chromium') === false
+    ) {
+        // In case IndexedDB was used as cache storage, remove it.
+        indexedDB.deleteDatabase(STORAGE_NAME);
         return vAPI.cacheStorage;
     }
 
-    const STORAGE_NAME = 'uBlock0CacheStorage';
     let db;
     let pendingInitialization;
     let dbByteLength;
 
-    let get = function get(input, callback) {
+    const get = function get(input, callback) {
         if ( typeof callback !== 'function' ) { return; }
         if ( input === null ) {
             return getAllFromDb(callback);
@@ -69,23 +78,23 @@
         return getFromDb(toRead, output, callback);
     };
 
-    let set = function set(input, callback) {
+    const set = function set(input, callback) {
         putToDb(input, callback);
     };
 
-    let remove = function remove(key, callback) {
+    const remove = function remove(key, callback) {
         deleteFromDb(key, callback);
     };
 
-    let clear = function clear(callback) {
+    const clear = function clear(callback) {
         clearDb(callback);
     };
 
-    let getBytesInUse = function getBytesInUse(keys, callback) {
+    const getBytesInUse = function getBytesInUse(keys, callback) {
         getDbSize(callback);
     };
 
-    let api = {
+    const api = {
         get,
         set,
         remove,
@@ -94,7 +103,7 @@
         error: undefined
     };
 
-    let genericErrorHandler = function(ev) {
+    const genericErrorHandler = function(ev) {
         let error = ev.target && ev.target.error;
         if ( error && error.name === 'QuotaExceededError' ) {
             api.error = error.name;
@@ -102,10 +111,10 @@
         console.error('[%s]', STORAGE_NAME, error && error.name);
     };
 
-    function noopfn() {
+    const noopfn = function () {
-    }
+    };
 
-    let getDb = function getDb() {
+    const getDb = function getDb() {
         if ( db instanceof IDBDatabase ) {
             return Promise.resolve(db);
         }
@@ -165,7 +174,7 @@
         return pendingInitialization;
     };
 
-    let getFromDb = function(keys, keyvalStore, callback) {
+    const getFromDb = function(keys, keyvalStore, callback) {
         if ( typeof callback !== 'function' ) { return; }
         if ( keys.length === 0 ) { return callback(keyvalStore); }
         let promises = [];
@@ -202,7 +211,7 @@
         });
     };
 
-    let visitAllFromDb = function(visitFn) {
+    const visitAllFromDb = function(visitFn) {
         getDb().then(( ) => {
             if ( !db ) { return visitFn(); }
             let transaction = db.transaction(STORAGE_NAME);
@@ -221,7 +230,7 @@
         });
     };
 
-    let getAllFromDb = function(callback) {
+    const getAllFromDb = function(callback) {
         if ( typeof callback !== 'function' ) { return; }
         let promises = [];
         let keyvalStore = {};
@@ -245,7 +254,7 @@
         });
     };
 
-    let getDbSize = function(callback) {
+    const getDbSize = function(callback) {
         if ( typeof callback !== 'function' ) { return; }
         if ( typeof dbByteLength === 'number' ) {
             return Promise.resolve().then(( ) => {
@@ -280,7 +289,7 @@
     //   https://developer.mozilla.org/en-US/docs/Web/API/IDBDatabase/transaction
     //   https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/put
 
-    let putToDb = function(keyvalStore, callback) {
+    const putToDb = function(keyvalStore, callback) {
         if ( typeof callback !== 'function' ) {
             callback = noopfn;
         }
@@ -326,7 +335,7 @@
         });
     };
 
-    let deleteFromDb = function(input, callback) {
+    const deleteFromDb = function(input, callback) {
         if ( typeof callback !== 'function' ) {
             callback = noopfn;
         }
@@ -356,7 +365,7 @@
         });
     };
 
-    let clearDb = function(callback) {
+    const clearDb = function(callback) {
         if ( typeof callback !== 'function' ) {
             callback = noopfn;
         }
@@ -383,6 +392,57 @@
     // prime the db so that it's ready asap for next access.
     getDb(noopfn);
 
+    // https://github.com/uBlockOrigin/uBlock-issues/issues/328
+    //   Detect whether browser.storage.local was used as cache storage,
+    //   and if so, move cache-related entries to the new storage.
+    {
+        const srcStorage = vAPI.cacheStorage;
+        const desStorage = api;
+        srcStorage.get(
+            [ 'assetCacheRegistry', 'assetSourceRegistry' ],
+            bin => {
+                if (
+                    bin instanceof Object === false ||
+                    bin.assetSourceRegistry instanceof Object === false
+                ) {
+                    return;
+                }
+                desStorage.set(bin);
+                const toRemove = [
+                    'assetCacheRegistry',
+                    'assetSourceRegistry',
+                    'resourcesSelfie',
+                    'selfie'
+                ];
+                let toMigrate = 0;
+                const setEntry = function(assetKey, bin) {
+                    if (
+                        bin instanceof Object &&
+                        bin[assetKey] !== undefined
+                    ) {
+                        desStorage.set(bin);
+                    }
+                    toMigrate -= 1;
+                    if ( toMigrate === 0 ) {
+                        srcStorage.remove(toRemove);
+                    }
+                };
+                for ( const key in bin.assetCacheRegistry ) {
+                    if ( bin.assetCacheRegistry.hasOwnProperty(key) === false ) {
+                        continue;
+                    }
+                    const assetKey = 'cache/' + key;
+                    srcStorage.get(assetKey, setEntry.bind(null, assetKey));
+                    toMigrate += 1;
+                    toRemove.push(assetKey);
+                }
+                if ( toMigrate === 0 ) {
+                    srcStorage.remove(toRemove);
+                }
+            }
+        );
+    }
+
     return api;
 }());
 

src/js/lz4.js

@@ -198,7 +198,11 @@ return {
                 data: decodeValue(result.key, result.data) || result.data
             };
         });
-    }
+    },
+    relinquish: function() {
+        ttlDelay = 1;
+        ttlManage(0);
+    },
 };
 
 /******************************************************************************/

src/js/start.js

@@ -53,6 +53,13 @@ vAPI.app.onShutdown = function() {
 // - Schedule next update operation.
 
 var onAllReady = function() {
+    // Ensure that the resources allocated for decompression purpose (likely
+    // large buffers) are garbage-collectable immediately after launch.
+    // Otherwise I have observed that it may take quite a while before the
+    // garbage collection of these resources kicks in. Relinquishing as soon
+    // as possible ensure minimal memory usage baseline.
+    µb.lz4Codec.relinquish();
+
     µb.webRequest.start();
     initializeTabs();
 

src/js/storage.js

@@ -608,15 +608,15 @@
     if ( this.loadingFilterLists ) { return; }
     this.loadingFilterLists = true;
 
-    var µb = this,
+    const µb = µBlock;
-        filterlistsCount = 0,
+    const loadedListKeys = [];
-        loadedListKeys = [];
+    let filterlistsCount = 0;
 
     if ( typeof callback !== 'function' ) {
         callback = this.noopFunc;
     }
 
-    var onDone = function() {
+    const onDone = function() {
         µb.staticNetFilteringEngine.freeze();
         µb.staticExtFilteringEngine.freeze();
         µb.redirectEngine.freeze();
@@ -632,17 +632,19 @@
         callback();
 
         µb.selfieManager.destroy();
+        µb.lz4Codec.relinquish();
+
         µb.loadingFilterLists = false;
     };
 
-    var applyCompiledFilters = function(assetKey, compiled) {
+    const applyCompiledFilters = function(assetKey, compiled) {
-        var snfe = µb.staticNetFilteringEngine,
+        const snfe = µb.staticNetFilteringEngine;
-            sxfe = µb.staticExtFilteringEngine,
+        const sxfe = µb.staticExtFilteringEngine;
-            acceptedCount = snfe.acceptedCount + sxfe.acceptedCount,
+        let acceptedCount = snfe.acceptedCount + sxfe.acceptedCount,
             discardedCount = snfe.discardedCount + sxfe.discardedCount;
         µb.applyCompiledFilters(compiled, assetKey === µb.userFiltersPath);
         if ( µb.availableFilterLists.hasOwnProperty(assetKey) ) {
-            var entry = µb.availableFilterLists[assetKey];
+            const entry = µb.availableFilterLists[assetKey];
             entry.entryCount = snfe.acceptedCount + sxfe.acceptedCount -
                 acceptedCount;
             entry.entryUsedCount = entry.entryCount -
@@ -651,7 +653,7 @@
         loadedListKeys.push(assetKey);
     };
 
-    var onCompiledListLoaded = function(details) {
+    const onCompiledListLoaded = function(details) {
         applyCompiledFilters(details.assetKey, details.content);
         filterlistsCount -= 1;
         if ( filterlistsCount === 0 ) {
@@ -659,7 +661,7 @@
         }
     };
 
-    var onFilterListsReady = function(lists) {
+    const onFilterListsReady = function(lists) {
         µb.availableFilterLists = lists;
 
         µb.redirectEngine.reset();
@@ -672,8 +674,8 @@
         // because it *may* happens that some load operations are synchronous:
         // This happens for assets which do not exist, ot assets with no
         // content.
-        var toLoad = [];
+        const toLoad = [];
-        for ( var assetKey in lists ) {
+        for ( const assetKey in lists ) {
             if ( lists.hasOwnProperty(assetKey) === false ) { continue; }
             if ( lists[assetKey].off ) { continue; }
             toLoad.push(assetKey);
@@ -683,7 +685,7 @@
             return onDone();
         }
 
-        var i = toLoad.length;
+        let i = toLoad.length;
         while ( i-- ) {
             µb.getCompiledFilterList(toLoad[i], onCompiledListLoaded);
         }
@@ -1021,6 +1023,7 @@
             staticExtFilteringEngine: µb.staticExtFilteringEngine.toSelfie()
         });
         µb.cacheStorage.set({ selfie: selfie });
+        µb.lz4Codec.relinquish();
     };
 
     let load = function(callback) {