@related: [[8139]] [[Serial]] [[8250]] [[5451]]

[[AmiloA]] :


==== too much work ====

  Serial 8250: too much work for irq 11 # this happend on mouse detection on [[Debian]]

==== IRQ-11 is eating CPU : top 1st ====
  # top 
  3485 root     -51  -5     0    0    0 S 30.1  0.0   7:34.20 IRQ-11

<code>
cat /proc/asound/card0/pcm0p/sub0/hw_params
access: RW_INTERLEAVED
format: S16_LE
subformat: STD
channels: 2
rate: 48000 (48000/1)
period_size: 1024
buffer_size: 16384

 cat  /etc/asound.conf
# http://rzr.online.fr/q/irq-11
pcm.!default {
 type plug
 slave.pcm {
  type dmix
  ipc_key 1024
  slave {
   pcm "hw:0,0"
   rate 44100
  }
 }
}
#eof "/etc/asound.conf"

lsmod | grep snd | cut -d' ' -f 1 | xargs sudo modprobe -r
sudo modprobe -v  snd_ali5451

cat /proc/asound/card0/pcm0p/sub0/hw_params
access: MMAP_INTERLEAVED
format: S16_LE
subformat: STD
channels: 2
rate: 44100 (44100/1)
period_size: 5513
buffer_size: 16384

</code>

==== messages ====

  dmesg | grep 11 | grep -i irq
  Jun 20 14:52:00 nrv kernel: Yenta: ISA IRQ mask 0x0020, PCI irq 11
  Jun 20 14:52:00 nrv kernel: PCI: setting IRQ 11 as level-triggered

@tag: [[DSDT]]

<code>
sudo cat  /proc/3088/status 
Name:	IRQ-11
State:	S (sleeping)
Tgid:	3088
Pid:	3088
PPid:	2
TracerPid:	0
Uid:	0	0	0	0
Gid:	0	0	0	0
FDSize:	32
Groups:	
Threads:	1
SigQ:	0/5879
SigPnd:	0000000000000000
ShdPnd:	0000000000000000
SigBlk:	0000000000000000
SigIgn:	ffffffffffffffff
SigCgt:	0000000000000000
CapInh:	0000000000000000
CapPrm:	ffffffffffffffff
CapEff:	fffffffffffffeff
CapBnd:	ffffffffffffffff
voluntary_ctxt_switches:	23758359
nonvoluntary_ctxt_switches:	0
</code>


==== misc ====

  * http://ubuntuforums.org/showthread.php?t=598793