kdeconnect-powersave-keepalive

Increase TCP keepalive timeout for longer battery life.

KDE Connect in Plasma desktop sends TCP keepalive messages every 5 seconds after connection has idled for 10 seconds, which drains paired phone battery at faster rate. https://bugs.kde.org/show_bug.cgi?id=441830

This workaround makes KDE Connect TCP keepalive timeout configurable. The default is set to 9 minutes.

Example of KDE Connect TCP keepalive messages:

05:09:30.783016 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544842155 ecr 2754153561], length 0
05:09:30.816512 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754153594 ecr 2544842156], length 0
05:09:41.018310 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544852390 ecr 2754153594], length 0
05:09:41.062820 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754163840 ecr 2544842156], length 0
05:09:51.258606 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544862631 ecr 2754163840], length 0
05:09:51.304018 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754174082 ecr 2544842156], length 0
05:10:01.498581 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544872871 ecr 2754174082], length 0
05:10:02.019323 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754182723 ecr 2544842156], length 0
05:10:12.250315 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544883622 ecr 2754182723], length 0
05:10:17.370580 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544888743 ecr 2754182723], length 0
05:10:17.383432 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754184063 ecr 2544842156], length 0
05:10:27.610478 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544898983 ecr 2754184063], length 0
05:10:32.730605 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544904103 ecr 2754184063], length 0
05:10:33.353527 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754185414 ecr 2544842156], length 0
05:10:43.482308 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544914854 ecr 2754185414], length 0
05:10:48.602579 IP workstation.32990 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2544919975 ecr 2754185414], length 0
05:10:48.650261 IP OnePlus-7T-Pro.1716 > workstation.32990: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2754190695 ecr 2544842156], length 0

Example of KDE Connect TCP keepalive messages with the workaround installed:

05:35:15.633953 IP OnePlus-7T-Pro.1716 > workstation.33000: Flags [.], ack 1449, win 176, options [nop,nop,TS val 2755026524 ecr 2546387004], length 0
05:35:15.634148 IP OnePlus-7T-Pro.1716 > workstation.33000: Flags [.], ack 2062, win 181, options [nop,nop,TS val 2755026524 ecr 2546387004], length 0
05:35:15.671758 IP workstation.33000 > OnePlus-7T-Pro.1716: Flags [.], ack 121, win 83, options [nop,nop,TS val 2546387044 ecr 2755026562], length 0
05:35:15.695753 IP workstation.33000 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2546387068 ecr 2755026586], length 0
05:35:15.731208 IP OnePlus-7T-Pro.1716 > workstation.33000: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2755026621 ecr 2546387068], length 0
05:44:34.586547 IP workstation.33000 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2546945959 ecr 2755026621], length 0
05:44:34.733266 IP OnePlus-7T-Pro.1716 > workstation.33000: Flags [.], ack 3480, win 187, options [nop,nop,TS val 2755514995 ecr 2546387068], length 0
05:46:12.656676 IP OnePlus-7T-Pro.1716 > workstation.33000: Flags [.], ack 4807, win 204, options [nop,nop,TS val 2755526826 ecr 2547043949], length 0
05:55:13.562665 IP workstation.33000 > OnePlus-7T-Pro.1716: Flags [.], ack 1285, win 83, options [nop,nop,TS val 2547584935 ecr 2755526826], length 0
05:55:13.648939 IP OnePlus-7T-Pro.1716 > workstation.33000: Flags [.], ack 4807, win 204, options [nop,nop,TS val 2755710185 ecr 2547043949], length 0

Usage

The workaround patches kdeconnectd ELF object to make it load the shared library built from this code. Using sudo command may be necessary to install and uninstall.

Clone, build and test

$ git clone [email protected]:max0x7ba/kdeconnect-powersave-keepalive.git
$ cd kdeconnect-powersave-keepalive
$ make

Install

$ sudo make install

Status

$ make status

Uninstall

$ sudo make uninstall

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Copyright (c) 2022 Maxim Egorushkin. MIT License. See the full licence in file LICENSE.