[linux-audio-user] Were's the weak link?

Hi,

I installed the Indigo IO card on my FC5/CCRMA system. I've done
everything I could think (or was suggested) to optimize my system to
allow for smooth, uninterrupted recording, including buying a 7200rpm
drive, tunning my hard disk, trying different 'Frames/Period' and
'Periods/Buffer' settings in qjackctl. My BIOS dosen't allow for
reordering of IRQs, so I disabled any peripheral that I absolutly could
do without, but I'm still having problems.

I'm running ecasound and jackd (both with realtime priorities). When
recording or in playback, sometimes I hear disruptions, but they don't
always end up in the actual recording. But there are *always* a few
noticeable pops, clicks or even loss of data in the actual
recorded audio files.

Can anyone spot where the "weak link" is in my system. I put in this
post (what I believe) is the most relevant information...

My system...
Dell Precision M50 laptop
2 GHz Processor
1 Gig Ram
2.6.16-1.2080.16.rrt.rhfc5.ccrma
7200rpm hard drive

'cat /proc/interrupts' (before disabling peripherals) shows:

   0: 3945911 XT-PIC [........N/ 0] pit
   1: 2898 XT-PIC [........./ 6] i8042
   2: 0 XT-PIC [........N/ 0] cascade
   5: 16931 XT-PIC [........./ 0] Intel 82801CA-ICH3 Modem, Intel
82801CA-ICH3
   7: 4 XT-PIC [..P....../ 0] parport0
   8: 1 XT-PIC [........./ 0] rtc
   9: 2 XT-PIC [........./ 0] acpi
  11: 8900 XT-PIC [........./ 0] yenta, yenta, yenta, pcmcia2.0,
Indigo IO, uhci_hcd:usb1, uhci_hcd:usb2, ohci1394
  12: 78714 XT-PIC [........./ 6] i8042
  14: 74419 XT-PIC [........./ 1] ide0
NMI: 0
LOC: 0
ERR: 0
MIS: 0

'/sbin/hdparm /dev/hda' shows...

  multcount = 16 (on)
  IO_support = 3 (32-bit w/sync)
  unmaskirq = 0 (off)
  using_dma = 1 (on)
  keepsettings = 0 (off)
  readonly = 0 (off)
  readahead = 256 (on)
  geometry = 16383/255/63, sectors = 117210240, start = 0

(3 reads of) 'hdparm -Tt /dev/hda'...

/dev/hda:
  Timing cached reads: 1368 MB in 2.00 seconds = 683.60 MB/sec
  Timing buffered disk reads: 112 MB in 3.03 seconds = 36.93 MB/sec
/dev/hda:
  Timing cached reads: 1368 MB in 2.00 seconds = 682.87 MB/sec
  Timing buffered disk reads: 120 MB in 3.02 seconds = 39.68 MB/sec
/dev/hda:
  Timing cached reads: 1368 MB in 2.00 seconds = 683.64 MB/sec
  Timing buffered disk reads: 120 MB in 3.02 seconds = 39.75 MB/sec

Thanks,
Rocco
Received on Sat Jan 20 12:15:02 2007