742849 - Disable AvailableMemoryTracker tracker on x86-64

Status: RESOLVED FIXED

(Core :: General, defect)

Description

[Justin Lebar (not reading bugmail)]

Once bug 742491 lands, we'll have a (hopefully) thread-safe implementation of WindowsDllInterceptor::AddHook for the functions that AvailableMemoryTracker overrides.

But we won't have a similar fix for x86-64.  Until we do, we should just disable the AvailableMemoryTracker there.  It's doing minimal good, anyway.

Comment 1

[Mozilla RelEng Bot]

Try run for 2c455f12a9f2 is complete.
Detailed breakdown of the results available here:
    https://tbpl.mozilla.org/?tree=Try&rev=2c455f12a9f2
Results (out of 50 total builds):
    success: 43
    warnings: 7
Builds (or logs if builds failed) available at:
http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/[e-mail]-2c455f12a9f2

Comment 2

[Justin Lebar (not reading bugmail)]

Attachment: Patch v1

Comment 3

[(no longer active)]

https://hg.mozilla.org/mozilla-central/rev/e7eab0a18edd

Comment 4

[Daniel C]

What's the distribution of total RAM like for 32-bit operating systems vs 64-bit operating systems? I assume Telemetry provides the necessary data.

I see quite a few 64-bit machines (with Windows 7 64-bit) sold with 2 GB of RAM. I don't know if that is less than your definition of "fair bit of physical memory".

Comment 5

[Justin Lebar (not reading bugmail)]

This wasn't really a decision based on hardware specs.  I disabled a fringe feature (low-memory detection) in favor of stability.

I have no way to make the code, as it exists, thread-safe on 64-bit.  If we figure it out (it's a fair bit of tricky work, and win64 isn't even tier 1), I'll gladly turn the feature back on.

Comment 6

[Justin Lebar (not reading bugmail)]

For the sake of completeness, I'm looking for our telemetry on physical memory.  I could have sworn we collect it, but I'm not seeing it in the dashboard.

Comment 7

[Justin Lebar (not reading bugmail)]

We do collect physical memory size, but we don't surface it in the telemetry dashboards.  :(