I just got this watch a few weeks ago. I've been dealing with battery drain since then. I finally took time out of my day to figure this out. After about half of a day I finally found that when the "Show on Now bar when media is playing on phone" is enabled, it is hammering the watch and keeping the CPU awake.
I ran a dumpsys battery stats and saved it to my computer but here are the 3 'Key' outputs.
With Media Controls ON and “Show on Now bar” ON, my watch recorded approximately 58,000–60,000 bluetooth_timer wakeups (~80 per minute), around 75,000–78,000 bt_read_wake_lock events (~100 per minute), and about 1,400 bt_mbox_irq_wlock activations (~17 per minute) during a 10–12 minute playback test. This high frequency of Bluetooth wake events aligns with the excessive battery drain I am experiencing.
With Media Controls ON and “Show on Now bar” OFF, the same playback test resulted in only about 1,400–1,600 bluetooth_timer wakeups (~1–2 per minute), roughly 2,300–2,500 bt_read_wake_lock events (~3–4 per minute), and about 35–40 bt_mbox_irq_wlock activations (~0.5 per minute). This is consistent with my normal low-drain baseline.
With Media Controls OFF entirely, the playback test showed about 1,200–1,500 bluetooth_timer wakeups (~1–2 per minute), around 2,000–3,000 bt_read_wake_lock events (~3–4 per minute), and about 30–40 bt_mbox_irq_wlock activations (~0.5 per minute), confirming that the baseline drain is normal without the Now bar active.
I know my Galaxy Watch didn't have this issue and I'm glad to have a finding. But this is a battery hog and its a feature I heavily use most of my day. Any help here?
Update to this post. Im addition to the steps above, I also went into watch developer tools and turned off logging buffer, and made sure that tethering hardware acceleration is enabled on the phone via its own system developer tools.
Also, as a further update, the new firmware release recently, L320XXS1AYH7, has so far improved my battery life. Granted, I still have the other settings set to reduce the battery further set (now bar off amd reduced notifications and apps), but today I had it off charger for about 11 hours and saw a drop of only 21% (2% an hour) no sleeping run yet but much improved from the factory image L320XXU1AYFE (4 - 5% an hour), and the first August update, L320XXU1AYG4 (3 - 3.5% an hour) I'm still testing but looks like this newest update is much improved.
