[mythtv-users] Enable DMA

[Yan-Fa Li]

On 3/22/07, Mitch Gore <mitchell.gore at gmail.com> wrote:
> Hi,
>
> I am trying to enable DMA on my HD Myth box to increase performance.  It
> works fine not but I have read so much about how DMA increases performance
> so i figured I would give it a shot...
>

Just check the output of dmesg and search for libata.  It should
indicate that the drive has DMA enabled.  For example:

libata version 2.00 loaded.
ata_piix 0000:00:1f.2: version 2.00ac7
ata_piix 0000:00:1f.2: MAP [ P0 P2 IDE IDE ]
ACPI: PCI Interrupt 0000:00:1f.2[C] -> GSI 20 (level, low) -> IRQ 22
PCI: Setting latency timer of device 0000:00:1f.2 to 64
ata1: SATA max UDMA/133 cmd 0x1F0 ctl 0x3F6 bmdma 0xFFA0 irq 14
ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0xFFA8 irq 15
scsi0 : ata_piix
ata1.00: ATA-7, max UDMA7, 156250000 sectors: LBA48 NCQ (depth 0/32)
ata1.00: ata1: dev 0 multi count 8
ata1.00: configured for UDMA/133
scsi1 : ata_piix
ata2.00: ATAPI, max UDMA/33
ata2.00: configured for UDMA/33
scsi 0:0:0:0: Direct-Access     ATA      SAMSUNG HD080HJ/ ZH10 PQ: 0 ANSI: 5
SCSI device sda: 156250000 512-byte hdwr sectors (80000 MB)