[mythtv-users] Slightly OT: Frame drops

[Ian Trider]

Hello,

I was wondering if anyone had some specific advice about frame drops
on my MythTV system.  I am using a Hauppauge PVR-350 and PVR-250. 
Output is by the PVR-350.  The processor is a 2.66ghz Celeron, 256MB
of RAM.  CPU usage is not even notable while recording.  However, I am
getting framedrops.  I'm not quite sure why, since hdparm seems to
suggest that my hard drive is configured properly.  I'm using 3mbit/s
for bitrate, so when hdparm says I have a throughput of 50MB/s I fail
to see why this would happen.

The frame drops only occur when recording two programs at once.

Here is what hdparm says:

[root at mythtv mnt]# hdparm -Tt /dev/hda

/dev/hda:
 Timing buffer-cache reads:   1508 MB in  2.00 seconds = 752.98 MB/sec
 Timing buffered disk reads:  156 MB in  3.02 seconds =  51.61 MB/sec


.. and info about the Hard drive:

[root at mythtv mnt]# hdparm -I /dev/hda

/dev/hda:

ATA device, with non-removable media
        Model Number:       ST380011A
        Serial Number:      5JVEX96Y
        Firmware Revision:  8.01
Standards:
        Used: ATA/ATAPI-6 T13 1410D revision 2
        Supported: 6 5 4 3
Configuration:
        Logical         max     current
        cylinders       16383   16383
        heads           16      16
        sectors/track   63      63
        --
        CHS current addressable sectors:   16514064
        LBA    user addressable sectors:  156301488
        device size with M = 1024*1024:       76319 MBytes
        device size with M = 1000*1000:       80026 MBytes (80 GB)
Capabilities:
        LBA, IORDY(can be disabled)
        bytes avail on r/w long: 4      Queue depth: 1
        Standby timer values: spec'd by Standard, no device specific minimum
        R/W multiple sector transfer: Max = 16  Current = 16
        Recommended acoustic management value: 254, current value: 0
        DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5
             Cycle time: min=120ns recommended=120ns
        PIO: pio0 pio1 pio2 pio3 pio4
             Cycle time: no flow control=240ns  IORDY flow control=120ns
Commands/features:
        Enabled Supported:
           *    READ BUFFER cmd
           *    WRITE BUFFER cmd
           *    Look-ahead
           *    Write cache
           *    Power Management feature set
           *    SMART feature set
           *    Mandatory FLUSH CACHE command
           *    Device Configuration Overlay feature set
           *    DOWNLOAD MICROCODE cmd
           *    General Purpose Logging feature set
           *    SMART self-test
           *    SMART error logging
HW reset results:
        CBLID- above Vih
        Device num = 0 determined by CSEL
Checksum: correct


Any ideas?
-- 
Ian Trider
iantri at gmail.com