(using ubuntu-feisty).
on one (sony vaio pcg-fx-501) of my two laptops (same feisty on both) hald uses more than 40% of cpu all the time.
preventing the fan to stop and making the system slow. the other laptop doesn't have these symptoms.
in the laptop there are two pcmcia-cards (wlan and pcmcia-to-usb2 [with one external harddrive attached to it]).
edit: this problem remains, when i boot the laptop without the pcmcia-cards attached.
I don't know how to debug problems like these, so please tell me the information you need (and how to get them, maybe).
Top (it looks like this all the time, even shortly after reboot, having done nothing before...):
top - 18:29:47 up 1:14, 2 users, load average: 2.22, 2.34, 2.38
Tasks: 108 total, 4 running, 104 sleeping, 0 stopped, 0 zombie
Cpu(s): 71.3%us, 25.4%sy, 0.2%ni, 2.1%id, 0.6%wa, 0.2%hi, 0.2%si, 0.0%st
Mem: 515880k total, 332264k used, 183616k free, 17784k buffers
Swap: 1212408k total, 0k used, 1212408k free, 200892k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4502 haldaemo 15 0 10640 9072 1724 R 41.5 1.8 32:20.73 hald
2414 root 21 -4 2780 1176 396 S 5.7 0.2 3:15.74 udevd
4435 root 15 0 1712 652 544 S 1.9 0.1 0:26.34 syslogd
7281 lars 15 0 18768 5312 4140 S 1.9 1.0 1:01.74 gnome-volume-ma
7364 lars 15 0 8416 3456 2864 S 1.9 0.7 0:53.82 gnome-vfs-daemo
8083 lars 15 0 19628 8676 7376 S 1.9 1.7 0:38.19 battstat-applet
1 root 15 0 1692 540 456 S 0.0 0.1 0:01.83 init
2 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0
p.s.: it's not a duplicate of this bug:
https://launchpad.net/distros/ubuntu/+source/gnome-vfs2/+bug/54684
i installed the provided packages and nothing changed.
i found the problem:
it's the sonypi-module. this is not working properly with vaio-laptops of the fs-series.
deleted the module from the modules-directory, so it doesn't get loaded at boot-time.
problem went away.
though this shouldn't be the solution for the average user... ;)