Hi, I notice a regression report on Bugzilla [1]. Quoting from it: > This commit improves power saving - it enables the kernel to achieve package C8. To achieve package C8, 3 Ubuntu VMD commits must be applied as well. The combined patch for the 3 Ubuntu VMD commits is attached (just in case). Package C8 lowers power usage on the laptop from 5.6W to 2.6W. > > However, a side-effect of this commit is that CPU usage for irq/155-rtw88_pci has increased noticeably. This commit was introduced in 6.4-rc6. To confirm this commit is the cause, a branch was created from 6.4-rc5. This commit and the 3 Ubuntu VMD commits were applied. The resulting kernel was built and tested - it can achieve package C8 and exhibits the increased CPU usage on irq/155-rtw88_pci. > > Booting and running top for 30 min with the system otherwise idle, gives these results for CPU on irq/155-rtw88_pci: > 6.4-rc5 - 00:02.9, mostly 0% and 0.3% displayed > patched rc5 - 00:13.4, mostly 0.7% and 1.0% displayed > By comparison, an 8th Gen Dell with an Intel WIFI has CPU usage of 00:01.7 under the same conditions. > > Laptop is a HP 15s-fq4011TU 11th Gen (Tiger Lake) Intel with (from lspci) Realtek Semiconductor Co., Ltd. RTL8822CE 802.11ac PCIe Wireless Network Adapter and Intel Corporation Volume Management Device NVMe RAID Controller. > > Ubuntu bug https://bugs.launchpad.net/ubuntu/+source/linux-hwe-6.2/+bug/2025040 provides further background. > > Please advise if I can assist with further testing. See Bugzilla for the full thread and attached proposed patch(es) that fix this regression. Anyway, I'm adding this regression to be tracked by regzbot: #regzbot introduced: 26a125f550a3bf https://bugzilla.kernel.org/show_bug.cgi?id=217828 #regzbot title: correcting SUPPORTS_DYNAMIC_PS calculation for rtw88 increases CPU utilization #regzbot link: https://bugs.launchpad.net/ubuntu/+source/linux-hwe-6.2/+bug/2025040 Thanks. [1]: https://bugzilla.kernel.org/show_bug.cgi?id=217828 -- An old man doll... just what I always wanted! - Clara
