100% cpu usage on machine idle

[mai ling]

* installed xrdp and icewm so I can remote desktop to a decent minimal graphical environment for WSL1
* logged in using mstsc.exe
* two days later found the laptop warm and laptop charger hot.

the cause appears to be ibus-daemon:

ubuntu@WSL1:~$ top -b -n 1 | head
top - 11:15:40 up 2 days, 31 min, 0 users, load average: 0.52, 0.58, 0.59
Tasks: 76 total, 1 running, 75 sleeping, 0 stopped, 0 zombie
%Cpu(s): 36.1 us, 23.0 sy, 0.0 ni, 41.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 16238.3 total, 8026.2 free, 7988.2 used, 224.0 buff/cache
MiB Swap: 32768.0 total, 32587.6 free, 180.4 used. 8119.6 avail Mem

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 2120 ubuntu 20 0 464592 4460 3500 S 400.0 0.0 2726:09 ibus-daemon
    1 root 20 0 8940 328 284 S 0.0 0.0 0:00.06 init
    7 root 20 0 8944 228 184 S 0.0 0.0 0:00.01 init

on windows side:

C:\WINDOWS\system32>powershell
Windows PowerShell
Copyright (C) Microsoft Corporation. All rights reserved.

Try the new cross-platform PowerShell https://aka.ms/pscore6

PS C:\WINDOWS\system32> Get-Counter -ErrorAction SilentlyContinue '\Process(*)\% Processor Time' | Select-Object -ExpandProperty countersamples| Select-Object -Property instancename, cookedvalue| ? {$_.instanceName -notmatch "^(idle|_total|system)$"} | Sort-Object -Property cookedvalue -Descending| Select-Object -First 10| ft InstanceName,@{L='CPU';E={($_.Cookedvalue/100/$env:NUMBER_OF_PROCESSORS).toString('P')}} -AutoSize

InstanceName CPU
------------ ---
ibus-daemon 25,25 %
taskmgr 1,17 %
explorer 0,39 %
powershell 0,39 %
init 0,00 %
svchost 0,00 %
msedge 0,00 %
wsftpcomhelper 0,00 %
mmc 0,00 %
msedge 0,00 %

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: ibus 1.5.26-4
ProcVersionSignature: Microsoft 4.4.0-19041.1237-Microsoft 4.4.35
Uname: Linux 4.4.0-19041-Microsoft x86_64
ApportVersion: 2.20.11-0ubuntu82.1
Architecture: amd64
CasperMD5CheckResult: unknown
Date: Thu Oct 6 11:08:53 2022
ExecutablePath: /usr/bin/ibus-daemon
RebootRequiredPkgs: Error: path contained symlinks.
SourcePackage: ibus
UpgradeStatus: Upgraded to jammy on 2022-08-08 (58 days ago)