[conspire] SATA HD transfers slow?

[Mark S Bilk]

Hi folks,

When I copy a 700-900MB file from my 1TB 7200 RPM SATA drive 
to my 1.5 TB 5900 RPM SATA drive (both Seagate Barracudas) the 
transfer rate varies from 8 to 29 MB/sec. (8, 11, 27, 29MB/sec
in four tests).  I don't know what causes the variation.  
I get similar rates transferring large files between one of the
internal drives and a Seagate FreeAgent Desk 1TB USB2.0 drive.

The spec sheet says up to 120MB/sec sustained data transfer 
rate for the 7200 RPM drive, so the 5900 RPM one should do 
about 98MB/sec.  I think I should be getting 50-90MB/sec from 
one drive to the other.

All filesystems are standard ext3.  A transfer (done with cp 
or mc) always saturates 100% one of the cores of the AMD Athlon 64 
5200+ CPU.  I'm running OpenSuse 11.2, 32-bit kernel 
"2.6.31.12-0.2-desktop #1 SMP PREEMPT 2010-03-16", on an Asus 
M2N-E mobo with 8GB of RAM.  The mobo manual says the storage
controller is NVIDIA nForce 570 Ultra MCP.

Wondering if the transfers are CPU-bound because DMA might not 
be enabled, I ran (as root):

# hdparm -d /dev/sda

/dev/sda:
 HDIO_GET_DMA failed: Inappropriate ioctl for device

Same result for /dev/sdb.

lsmod listing follows.

Should I be getting faster transfers?  If so, how can I do it?

  Thanks in advance!
  
  Mark

Module                  Size  Used by
bluetooth             103524  0 
rfkill                 22772  1 bluetooth
ip6t_LOG                6468  8 
xt_tcpudp               3136  14 
xt_pkttype              1632  3 
ipt_LOG                 6276  8 
xt_limit                2692  16 
af_packet              23456  0 
edd                    10472  0 
snd_pcm_oss            51616  0 
snd_mixer_oss          19104  1 snd_pcm_oss
snd_seq                64784  0 
snd_seq_device          8620  1 snd_seq
ip6t_REJECT             5472  3 
nf_conntrack_ipv6      22036  4 
ip6table_raw            3008  1 
xt_NOTRACK              1632  4 
ipt_REJECT              3168  3 
xt_state                2208  8 
iptable_raw             2848  1 
iptable_filter          3616  1 
ip6table_mangle         4160  0 
nf_conntrack_netbios_ns     2560  0 
nf_conntrack_ipv4      11688  4 
nf_conntrack           84768  5 nf_conntrack_ipv6,xt_NOTRACK,xt_state,nf_conntrack_netbios_ns,nf_conntrack_ipv4
nf_defrag_ipv4          2112  1 nf_conntrack_ipv4
ip_tables              13392  2 iptable_raw,iptable_filter
ip6table_filter         3616  1 
ip6_tables             14832  4 ip6t_LOG,ip6table_raw,ip6table_mangle,ip6table_filter
x_tables               19524  11 ip6t_LOG,xt_tcpudp,xt_pkttype,ipt_LOG,xt_limit,ip6t_REJECT,xt_NOTRACK,ipt_REJECT,xt_state,ip_tables,ip6_tables
fuse                   74332  3 
loop                   17228  0 
dm_mod                 84900  0 
snd_hda_codec_analog    66400  1 
tuner_simple           16240  1 
tuner_types            14400  1 tuner_simple
tuner                  23492  1 
tvaudio                29276  0 
tda7432                 5720  0 
msp3400                31180  0 
ppdev                  10276  0 
bttv                  133428  0 
i2c_algo_bit            6884  1 bttv
btcx_risc               5288  1 bttv
saa7134               166220  0 
ir_common              49284  2 bttv,saa7134
v4l2_common            19328  6 tuner,tvaudio,tda7432,msp3400,bttv,saa7134
videodev               39168  7 tuner,tvaudio,tda7432,msp3400,bttv,saa7134,v4l2_common
v4l1_compat            16004  1 videodev
videobuf_dma_sg        14724  2 bttv,saa7134
videobuf_core          20164  3 bttv,saa7134,videobuf_dma_sg
tveeprom               12132  2 bttv,saa7134
nvidia               8895108  38 
floppy                 61220  0 
parport_pc             40356  0 
parport                39948  2 ppdev,parport_pc
snd_hda_intel          31776  9 
snd_hda_codec          94688  2 snd_hda_codec_analog,snd_hda_intel
snd_hwdep               8740  1 snd_hda_codec
snd_pcm                96324  5 snd_pcm_oss,snd_hda_intel,snd_hda_codec
asus_atk0110           13888  0 
forcedeth              60140  0 
k8temp                  4832  0 
snd_timer              25960  4 snd_seq,snd_pcm
snd                    75236  24 snd_pcm_oss,snd_mixer_oss,snd_seq,snd_seq_device,snd_hda_codec_analog,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_timer
snd_page_alloc         10600  2 snd_hda_intel,snd_pcm
pcspkr                  2784  0 
i2c_nforce2             8516  0 
button                  6608  0 
sg                     32884  0 
sr_mod                 17572  0 
cdrom                  40768  1 sr_mod
fan                     5028  0 
processor              50576  0 
ide_pci_generic         4036  0 
amd74xx                 6408  0 
ide_core              122540  2 ide_pci_generic,amd74xx
pata_amd               12356  0 
ata_generic             4836  0 
sata_nv                26284  4 
thermal                21084  0 
thermal_sys            18344  3 fan,processor,thermal