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.
The environment flavor is used to by uBO to for self-configuration.
For users with spoofed UA at the `about:config` level, this might
cause uBO to misconfigure itself. Avoid UA and strictly rely on
browserInfo() for looking up environment parameters.
The Promise chain was not properly designed for WASM module
loading. This became apparent when removing WASM modules
from Opera build[1].
The problem was that errors thrown by fetch() -- used to
load WASM modules -- were not properly handled.
[1] Opera refuses updating uBO if there are unrecognized file
types in the package, and `.wasm`/`.wat` files are not
recognized by Opera uploader.
Related issue:
- https://github.com/NanoAdblocker/NanoCore/issues/239
The erroneous behavior was to compute the URL of a sublist as
relative to the URL of the root list, which may differ from the
URL of a parent list.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/407
Both flavors will be stitched together into a single
`vapi-qebrequest.js` file.
The decision of which flavor to use will be made at runtime,
according to the browser environment.
Those spurious disconnections have been observed to occur at
uBO's launch time.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/403
I have observed that this fixes an issue observed on Firefox 64
(current stable).
The reported Waterfox issue *may* be fixed as a result. If not,
the issue he still considered fixed as Waterfox is not
officially supported.
I see the outside world still referring to these graphes as
reference material in arguments regarding uBO's efficiency.
I have no doubt uBO is more efficient than other content
blockers with similar capabilities, but using obsolete
measurement is not the proper way to make the point.
I may add new benchmarks but these are time-consuming
so for now it's best to remove this section based on outdated
materials.
