Re: kern/46325: wapbl + disk io = temporary system freeze

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

The following reply was made to PR kern/46325; it has been noted by GNATS.

From: Christoph Egger <Christoph_Egger%gmx.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost, 
 netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/46325: wapbl + disk io = temporary system freeze
Date: Thu, 12 Apr 2012 13:01:11 +0200

 On 04/12/12 12:45, Christoph Egger wrote:
 > The following reply was made to PR kern/46325; it has been noted by GNATS.
 >
 > From: Christoph Egger<Christoph_Egger%gmx.de@localhost>
 > To: gnats-bugs%NetBSD.org@localhost
 > Cc: Martin Husemann<martin%duskware.de@localhost>, 
 > kern-bug-people%netbsd.org@localhost,
 >   gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost
 > Subject: Re: kern/46325: wapbl + disk io = temporary system freeze
 > Date: Thu, 12 Apr 2012 12:40:50 +0200
 >
 >   On 04/12/12 11:50, Martin Husemann wrote:
 >   >  The following reply was made to PR kern/46325; it has been noted by 
 > GNATS.
 >   >
 >   >  From: Martin Husemann<martin%duskware.de@localhost>
 >   >  To: gnats-bugs%NetBSD.org@localhost
 >   >  Cc:
 >   >  Subject: Re: kern/46325: wapbl + disk io = temporary system freeze
 >   >  Date: Thu, 12 Apr 2012 11:47:51 +0200
 >   >
 >   >    Stupid questions, just to make sure we are not barking up the wrong 
 > tree:
 >   >
 >   >     - your underlying disk io speed is OK? (dmesg excerpts or bonnie++ 
 > runs
 >   >       would give hints)
 >
 >   wd0 at atabus1 drive 0
 >   wd0:<ST3500413AS>
 >   wd0: drive supports 16-sector PIO transfers, LBA48 addressing
 >   wd0: 465 GB, 969021 cyl, 16 head, 63 sec, 512 bytes/sect x 976773168 
 > sectors
 >   wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
 >
 >   that's ok.
 >
 >   pciide0 at pci0 dev 17 function 0: AMD Hudson SATA Controller (rev. 0x40)
 >   pciide0: bus-master DMA support present, but unused (no driver support)
 >   pciide0: primary channel configured to native-PCI mode
 >   pciide0: using ioapic0 pin 19 for native-PCI interrupt
 >   atabus0 at pciide0 channel 0
 >   pciide0: secondary channel configured to native-PCI mode
 >   atabus1 at pciide0 channel 1
 >
 >   eek, DMA support is missing in pciide0.
 
 Problem seems to be solved: I changed the BIOS SATA mode from IDE to AHCI.
 
 
 load averages:  0.95,  0.47,  0.19;               up 0+00:04:52 
    12:58:40
 135 threads: 18 idle, 111 sleeping, 2 zombie, 4 on CPU
 CPU0 states:  0.0% user,  0.0% nice,  9.4% system,  5.6% interrupt, 
 85.0% idle
 CPU1 states:  1.6% user,  0.0% nice,  4.4% system,  0.0% interrupt, 
 94.0% idle
 CPU2 states:  0.2% user,  0.0% nice,  0.0% system,  0.0% interrupt, 
 99.8% idle
 CPU3 states:  6.6% user,  0.0% nice, 68.1% system,  0.0% interrupt, 
 25.3% idle
 Memory: 783M Act, 16K Wired, 88M Exec, 177M File, 6852M Free
 Swap: 8171M Total, 8171M Free
 
    PID   LID     UID  PRI STATE      TIME   WCPU    CPU NAME      COMMAND
    483     1       0   26 CPU/3      0:36 74.88% 69.34% -         cvs
      0    63       0  124 syncer/1   0:02  6.15%  6.15% ioflush   [system]
 
 
 I am still puzzled why so much 'system' time is spent.
 
 Christoph