What apps other than Firefox might this have affected that badly (75% CPU usage)?
Newer versions of Thunderbird have been rendered completely unusable unless I exclude %userprofile%\AppData\Local\Thunderbird from real-time scans.
Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
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Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#12I would like anyone that considers Microsoft to be a recent champion of Open Source to reflect on corporate doublespeak. It's plausible that this bug was engineered as an attack on Firefox.
Have you any semblance of proof of this?
By the looks of it took Firefox a few years to figure out what the repro was, they reported it to MS, it was (very) promptly fixed and they were warned that the syscall they were using isn't being used as intended and they should consider changes to FF for future use cases.
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#13That's one way to look at it, but a very biased take. An equally valid take is that Firefox was calling an expensive platform feature too often, and even though it has been killing performance for years (possibly, for the entire history of the project) nobody noticed or bothered to fix it on the application side.
The platform feature in question was normally cheap and just made artificially expensive by Defender intercepting calls to it and blocking until analysis was performed. I don't think it's the FireFox' team's responsibility to be aware of and take into account arbitrary software intercepting system calls.
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#14I would like anyone that considers Microsoft to be a recent champion of Open Source to reflect on corporate doublespeak. It's plausible that this bug was engineered as an attack on Firefox.
What a weird take. If this bug was engineered as an attack on Firefox, then it seems like the project has been infiltrated by bad actors, because the bug comes from Firefox's codebase. Indeed, the developers themselves contradict your comment in the linked bug conversation:
> This problem has two sides: Microsoft was doing a lot of useless computations upon each event; and we are generating a lot of events. The combination is explosive. Now that Microsoft has done their part of the job (comment 82), we need to reduce our dependency to VirtualProtect.
(https://bugzilla.mozilla.org/show_bug.cgi?id=1441918#c90)
Compare how many calls other browsers make (this is also quoted in the link): Firefox was generating up to 46 times more (costly) events than Chrome. It is a bit ludicrous to shame Microsoft for the whole situation.
> Firefox with normal configuration: ~14000 events, 98% of which are PROTECTVM_LOCAL;
> Firefox with the preferences from comment 83: ~6500 events, 95% of which are PROTECTVM_LOCAL;
> Edge: ~2000 events, 91% of which are ALLOCVM_LOCAL;
> Chrome: ~300 events.
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#15That's one way to look at it, but a very biased take. An equally valid take is that Firefox was calling an expensive platform feature too often, and even though it has been killing performance for years (possibly, for the entire history of the project) nobody noticed or bothered to fix it on the application side.
The platform feature in question was normally cheap and just made artificially expensive by Defender intercepting calls to it and blocking until analysis was performed. I don't think it's the FireFox' team's responsibility to be aware of and take into account arbitrary software intercepting system calls.
Windows Defender real-time protection is enabled by default.
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#16[flagged]
You'd think they'd target Chrome (>60% market share on Desktop) rather than Firefox with < 8% market share.
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#17I would like anyone that considers Microsoft to be a recent champion of Open Source to reflect on corporate doublespeak. It's plausible that this bug was engineered as an attack on Firefox.
Do we have to assume negative intent every time something like this happens?
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#18I would like anyone that considers Microsoft to be a recent champion of Open Source to reflect on corporate doublespeak. It's plausible that this bug was engineered as an attack on Firefox.
This is a relic of Bill’s tenor. Satya is different in good way.
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#19That's one way to look at it, but a very biased take. An equally valid take is that Firefox was calling an expensive platform feature too often, and even though it has been killing performance for years (possibly, for the entire history of the project) nobody noticed or bothered to fix it on the application side.
The platform feature in question was normally cheap and just made artificially expensive by Defender intercepting calls to it and blocking until analysis was performed. I don't think it's the FireFox' team's responsibility to be aware of and take into account arbitrary software intercepting system calls.
> I don't think it's the FireFox' team's responsibility to be aware of and take into account arbitrary software intercepting system calls.
Per the bug report, Firefox was generating up to ~14,000 calls where Chrome was generating ~300, though.
Surely it is Firefox' team's responsibility to use system calls in a sane way, say not almost 50x more than the competition?
Re: Microsoft fixes 5-year-old Defender bug, reducing Firefox-related CPU use by 75%
#20I would like anyone that considers Microsoft to be a recent champion of Open Source to reflect on corporate doublespeak. It's plausible that this bug was engineered as an attack on Firefox.
It is amusing that anyone thinks a company with > 200K employees and probably 10K products is organized enough for something like this.