Bat Ledger Service uses 99% of CPU

Description

In the last weeks I noticed that Brave Browser Helper process is using a lot of CPU(~99%). Digging in the browser tools I found that Bat Ledger Service is taking all the CPU.

Test plan / Steps to Reproduce (edited by @bsclifton)

1. Install Brave, fresh profile
2. Enable rewards
3. Visit a page (website, twitter profile, etc)
4. Click BAT icon in omnibox

Actual result:

Reproduces how often:

Every time I open the browser.

Brave version (brave://version info)

Revision	fcea73228632975e052eb90fcf6cd1752d3b42b4-refs/branch-heads/3987@{#974}
OS	macOS Version 10.14.6 (Build 18G95)
JavaScript	V8 8.0.426.26
Flash	(Disabled)
User Agent	Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36
Command Line	/Applications/Brave Browser.app/Contents/MacOS/Brave Browser --enable-dom-distiller --disable-domain-reliability --no-pings --extension-content-verification=enforce_strict --extensions-install-verification=enforce --sync-url=https://no-thanks.invalid --enable-features=PasswordImport,WebUIDarkMode,SimplifyHttpsIndicator --disable-features=AutofillServerCommunication,VideoPlaybackQuality,AllowPopupsDuringPageUnload,SmsReceiver,AudioServiceOutOfProcess,NotificationTriggers,LookalikeUrlNavigationSuggestionsUI,WebXR,WebXrGamepadModule --flag-switches-begin --flag-switches-end --enable-audio-service-sandbox --disable-webrtc-apm-in-audio-service --disable-sync
Executable Path	/Applications/Brave Browser.app/Contents/MacOS/Brave Browser
Profile Path	/Users/hongoloco/Library/Application Support/BraveSoftware/Brave-Browser/Default

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? No
• Does the issue resolve itself when disabling Brave Rewards? No
• Is the issue reproducible on the latest version of Chrome? No

[kjozwiak]

Thanks for all the info. We’re currently looking into this as we speak. +1 from me as well.

I’ve noticed this on Friday when I updated to 1.8.11 CR: 80.0.3987.132 as I was a few days behind Nightly. After a bit of time, I started noticing that my machine started turning on the fans/overheating. This has been happening all weekend. As per the above, it’s due to the BAT Ledger Service using 100% CPU.

Reproduced using the following:

Brave | 1.8.11 Chromium: 80.0.3987.132 (Official Build) nightly (64-bit)
-- | --
Revision | fcea73228632975e052eb90fcf6cd1752d3b42b4-refs/branch-heads/3987@{#974}
OS | macOS Version 10.15.3 (Build 19D76)

CCing @rebron @NejcZdovc @mandar-brave @bsclifton @BrendanEich

[bsclifton]

Marked as release-notes/exclude since this has not made it to Release channel yet. Problem that is known is only in Beta/Dev/Nightly