Implement a plain string trie container class: STrieContainer.
Make use of STrieContainer where beneficial
Some filter buckets can grow quite large, and in such case
coalescing "trieable" filter classes into a single trie reduces
lookup performance and memory usage.
For instance, at time of commit, the filter bucket for the
`ad` keyword contains 919 entries[1].
Coalescing trieable filters of the same class into a single plain
string trie reduced the size of the bucket into 50 entries + two
tries which are scanned only once each whenever the bucket is
visited.
[1] Enter the following code at uBO's dev console:
µBlock.staticNetFilteringEngine.categories.get(0).get(µBlock.urlTokenizer.tokenHashFromString('ad'))
Refactor static network filtering engine code to make use of
ES6's syntactic sugar `class`.
Change first auto-update run from 7 to 5 minutes.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/416
The Chromium version of uBO has declared `unlimitedStorage` since the
extension was first published in 2014. Declaring this permission in
Firefox brings uBO inline with the Chromium version. I suspect some
reported errors could be caused by IndexedDB eviction due to the lack
of `unlimitedStorage` permission.
Additionally, a timeout has been added when uBO tries to access its
indexedDB storage. It's unclear whether this will help with the
mentioned related issue though, the root cause is still to be
identified.
Relocate workaround to the code responsible to compute filtering context, such
that the workaround will also be applied in other code paths, for example also
for webRequest.onHeadersReceived.
With the new PSL implementation, benchmarks do not show benefit
from caching the domain extracted from a hostname for later
reuse -- the caching seems to even add an overhead instead with
the new publicSuffixList implementation.
Default behavior is to fall back to an alternative backend
if the uBO-selected one is not available. However there will be
no fall back when the `cacheStorageAPI` is set to one specific
backend by the user.
The value of `suspendTabsUntilReady` was disregarded in Firefox and
uBO defaulted to always defer tab loading until it was ready.
This commit allows to disable the deferring of tab loading in
Firefox. The new valid values for `suspendTabsUntilReady` are:
- `unset`: leave it to the platform to pick the optimal
behavior (default)
- `no`: do no suspend tab loading at launch time
- `yes`: suspend tab loading at launch time
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/409
By default `indexedDB` is used in Firefox for purpose of cache storage
backend.
This commit allows to force the use of `browser.storage.local` instead
as cache storage backend. For this to happen, set `cacheStorageAPI` to
`browser.storage.local` in advanced settings.
Additionally, should `indexedDB` not be available for whatever reason,
uBO will automatically fallback to `browser.storage.local`.
These filters are to be considered obsolete since they can't be
matched against network requests in the webRequest API.
They were probably meant to work when ABP was pre-webext, which
means they are quite probably obsolete and there is no longer
a point for uBO to conveniently translate them into CSP directives.
This removes the derivation of FilterOrigin flavors from
FilterOrigin itself and simplify code paths. FilterOrigin
flavors are small specialized classes, no need to
overcomplicate with derivation.
Specifically, this removes an indirect call to reach the
match() method.
As seen at:
https://whotracks.me/blog/adblockers_performance_study.html
The requests.json.gz file can be downloaded from:
https://cdn.cliqz.com/adblocking/requests_top500.json.gz
Copy the file into ./tmp/requests.json.gz
If the file is present when you build uBO using `make-[target].sh` from
the shell, the resulting package will contain `./assets/requests.json`,
which will be looked-up by the method below to launch a benchmark
session.
From uBO's dev console, launch the benchmark:
µBlock.staticNetFilteringEngine.benchmark();
The usual browser dev tools can be used to obtain useful profiling
data, i.e. start the profiler, call the benchmark method from the
console, then stop the profiler when it completes.
Keep in mind that the measurements at the blog post above where obtained
with ONLY EasyList. The CPU reportedly used was:
https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-6600U+%40+2.60GHz&id=2608
Rename ./tmp/requests.json.gz to something else if you no longer want
./assets/requests.json in the build.
The motivation is to address the higher peak memory usage at launch
time with 3rd-gen HNTrie when a selfie was present.
The selfie generation prior to this change was to collect all
filtering data into a single data structure, and then to serialize
that whole structure at once into storage (using JSON.stringify).
However, HNTrie serialization requires that a large UintArray32 be
converted into a plain JS array, which itslef would be indirectly
converted into a JSON string. This was the main reason why peak
memory usage would be higher at launch from selfie, since the JSON
string would need to be wholly unserialized into JS objects, which
themselves would need to be converted into more specialized data
structures (like that Uint32Array one).
The solution to lower peak memory usage at launch is to refactor
selfie generation to allow a more piecemeal approach: each filtering
component is given the ability to serialize itself rather than to be
forced to be embedded in the master selfie. With this approach, the
HNTrie buffer can now serialize to its own storage by converting the
buffer data directly into a string which can be directly sent to
storage. This avoiding expensive intermediate steps such as
converting into a JS array and then to a JSON string.
As part of the refactoring, there was also opportunistic code
upgrade to ES6 and Promise (eventually all of uBO's code will be
proper ES6).
Additionally, the polyfill to bring getBytesInUse() to Firefox has
been revisited to replace the rather expensive previous
implementation with an implementation with virtually no overhead.
