kern/104624: Sound, mouse and keyboard badly interrupted while I/O (disk, net)

Alexander Best arundel at
Sun Dec 12 11:10:11 UTC 2010

The following reply was made to PR kern/104624; it has been noted by GNATS.

From: Alexander Best <arundel at>
To: bug-followup at
Subject: Re: kern/104624: Sound, mouse and keyboard badly interrupted while I/O (disk, net)
Date: Sun, 12 Dec 2010 11:03:05 +0000

 hi jaakko,
 i can confirm that a similar issue exists for me running a very recent HEAD
 snapshot on amd64. when the disk is performing heavy i/o (make -j8 buildworld
 e.g.) sound starts stuttering and the system goes semi-responsive. mostly the
 mouse input (usb) is lagging, but sometimes the cursor freezes in it's current
 position for 10 seconds or so. in addition to that mouse input seems to get
 corrupted and spontanious mouse clicks get generated. i talked to hps once and
 he suspected that some mice require a certain polling rate. since under heavy
 i/o the system seems unable to comply to that polling rate the mouse behavior
 becomes whacky. i see this behavior both under ULE and 4BSD. this is the
 output of vmstat -i on my system:
 interrupt                          total       rate
 irq16: vgapci0++                  644115          6
 irq18: uhci2 ehci0+               130730          1
 irq19: ath0 ahci0+              24562200        259
 irq20: hpet0                    85278624        900
 irq21: uhci1                     2478835         26
 irq256: ahci1                   22677130        239
 irq257: hdac0                    5554487         58
 Total                          141326121       1492
 this is my soundcard:
 hdac0 at pci0:0:27:0:	class=0x040300 card=0xa0021458 chip=0x293e8086 rev=0x02 hdr=0x00
     vendor     = 'Intel Corporation'
     device     = '82801IB/IR/IH (ICH9 Family) HD Audio Controller'
     class      = multimedia
     subclass   = HDA

More information about the freebsd-bugs mailing list