5 ms·

I feel like one thing that seldom gets mentioned is that there is a difference in battery life between the Pro and the Air. I have an M1 MBA and while the batte

by Fwirt 5y ago

I feel like one thing that seldom gets mentioned is that there is a difference in battery life between the Pro and the Air. I have an M1 MBA and while the battery life is very impressive I still go through about 10% of my battery per hour of simultaneous VMWare Horizon Client and Firefox (10 tabs, one playing music) with a little Zoom sprinkled in. If I just have Safari open I can definitely get a lot more out of the battery, but I feel like that's a little unrealistic. That being said it's still the best laptop I've ever owned and I don't have regrets about getting the Air, but when these battery life articles come up it's just assumed that everyone has the Pro.

floatingatoll 5y ago
To confirm, you reliably get 10 hours of battery life running VMware, Firefox, and Zoom?
- deleted 5y ago
  [deleted]
- Fwirt 5y ago
  I use AlDente to keep my battery between 80% and 20%. Zoom probably gets 30-60 min of usage during the day. If I start at 9 I usually have to plug in (hit 20%) around 2, so that's 60% in 5 hours. So probably 8-9 hours if I let it run all the way from 100% to 0%. It's not really a complaint about longevity, like I said it's above and beyond any other laptop I've owned, I just see many anecdotes of "I Zoom for 6 hours and my battery is at 90%!" and I find that hard to believe.
  - floatingatoll 5y ago
    One of Zoom’s most intensive CPU tasks is continuous H.264 encoding/decoding, which Apple has hardware accelerated and presumably made power efficient; so it isn’t valid to compare a VMware/Firefox workload to a Zoom workload in a vacuum, especially if the attendee is mostly facemuting (which saves further power in both encoding and webcam) or screensharing video with audio (which makes my 8-core Apple desktop turn on the heat-venting fans). Both workloads are possible, even just within a Zoom-only scenario, and anecdotes are generally insufficient to tell which is the case.
    - Fwirt 5y ago
      Interesting detail, thank you. I never did a dive into how well Zoom optimized for power consumption. Good things to keep in mind.
      - floatingatoll 5y ago
        The five relevant questions are, as best as I can remember right now: 1) Is the user's camera on, transmitting an H.264-encoded stream? 2) Is the user using virtual backgrounds, which have a CPU minimum requirement beyond that of the rest of Zoom? 3) Is the user screen sharing, transmitting an H.264-encoded stream, with or without the full-motion video checkbox enabled? 4) How many attendees are shown on the user's screen and are being H.264-decoded to the display? 5) Does Zoom use Apple's A/V interfaces for H.264 encoding and decoding, directly or indirectly, and has Apple (not Zoom!) improved the watts used for those operations on the M1 CPU? #5, at least, I can consider. I'm looking inside the Zoom macOS binary now and I see a variety of functions in aomhost that are, essentially, image and video stream processing functions, with custom code for _avx2 and _sse2, on my Intel Mac. Zoom supposedly released an M1 native update in December, but I don't (yet) know how to get the M1 client on my Intel Mac to inspect further. EDIT: Found the M1 client: https://zoom.us/download https://zoom.us/download, "Apple Silicon". In the M1 client, the framework aomhost, which contained x64-optimized function names, is absent; as well as libmpg123. Framework aomagent replaces ApplicationServices with ColorSync,CoreGraphics. So at least for #5, I suspect that Zoom is using Apple's encoding/decoding interfaces, since there's little chance they ported the third-party open source libraries to native macOS interfaces. They're still bundling OpenSSL 1.1.1k rather than using Apple's SSL interfaces, so presumably they only rewrote the MPEG interfaces because they had SSE/AVX optimizations.

by Fwirt 5y ago

floatingatoll 5y ago

To confirm, you reliably get 10 hours of battery life running VMware, Firefox, and Zoom?

deleted 5y ago
[deleted]
Fwirt 5y ago
I use AlDente to keep my battery between 80% and 20%. Zoom probably gets 30-60 min of usage during the day. If I start at 9 I usually have to plug in (hit 20%) around 2, so that's 60% in 5 hours. So probably 8-9 hours if I let it run all the way from 100% to 0%. It's not really a complaint about longevity, like I said it's above and beyond any other laptop I've owned, I just see many anecdotes of "I Zoom for 6 hours and my battery is at 90%!" and I find that hard to believe.
- floatingatoll 5y ago
  One of Zoom’s most intensive CPU tasks is continuous H.264 encoding/decoding, which Apple has hardware accelerated and presumably made power efficient; so it isn’t valid to compare a VMware/Firefox workload to a Zoom workload in a vacuum, especially if the attendee is mostly facemuting (which saves further power in both encoding and webcam) or screensharing video with audio (which makes my 8-core Apple desktop turn on the heat-venting fans). Both workloads are possible, even just within a Zoom-only scenario, and anecdotes are generally insufficient to tell which is the case.
  - Fwirt 5y ago
    Interesting detail, thank you. I never did a dive into how well Zoom optimized for power consumption. Good things to keep in mind.
    - floatingatoll 5y ago
      The five relevant questions are, as best as I can remember right now: 1) Is the user's camera on, transmitting an H.264-encoded stream? 2) Is the user using virtual backgrounds, which have a CPU minimum requirement beyond that of the rest of Zoom? 3) Is the user screen sharing, transmitting an H.264-encoded stream, with or without the full-motion video checkbox enabled? 4) How many attendees are shown on the user's screen and are being H.264-decoded to the display? 5) Does Zoom use Apple's A/V interfaces for H.264 encoding and decoding, directly or indirectly, and has Apple (not Zoom!) improved the watts used for those operations on the M1 CPU? #5, at least, I can consider. I'm looking inside the Zoom macOS binary now and I see a variety of functions in aomhost that are, essentially, image and video stream processing functions, with custom code for _avx2 and _sse2, on my Intel Mac. Zoom supposedly released an M1 native update in December, but I don't (yet) know how to get the M1 client on my Intel Mac to inspect further. EDIT: Found the M1 client: https://zoom.us/download https://zoom.us/download, "Apple Silicon". In the M1 client, the framework aomhost, which contained x64-optimized function names, is absent; as well as libmpg123. Framework aomagent replaces ApplicationServices with ColorSync,CoreGraphics. So at least for #5, I suspect that Zoom is using Apple's encoding/decoding interfaces, since there's little chance they ported the third-party open source libraries to native macOS interfaces. They're still bundling OpenSSL 1.1.1k rather than using Apple's SSL interfaces, so presumably they only rewrote the MPEG interfaces because they had SSE/AVX optimizations.