Run hdparm -Tt on the SATA drives. If you get I/O greater than, say, 8<br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
megabytes a second, then I'm pretty sure DMA is enabled (my experience<br>with older IDE drives was that they maxed out at about 4 megs per<br>second (at the most) if DMA was disabled, regardless of drive or CPU<br>speed). For example - on one system here "hdparm /dev/sdb" shows no<br>
way to control DMA, but when using "-Tt" shows a raw read rate of<br>about 74 megs/second (cached from controller is 220/megs/second), so<br>I'm pretty certain DMA IS enabled.<br><font color="#888888"><br>Calvin<br>
</font><div></div></blockquote><div><br>[root@mythtv ~]# hdparm -Tt /dev/sda<br><br>/dev/sda:<br> Timing cached reads: 1330 MB in 2.00 seconds = 665.24 MB/sec<br> Timing buffered disk reads: 76 MB in 3.05 seconds = 24.96 MB/sec<br>
[root@mythtv ~]# hdparm -Tt /dev/sdb<br><br>/dev/sdb:<br> Timing cached reads: 1516 MB in 2.00 seconds = 757.98 MB/sec<br> Timing buffered disk reads: 126 MB in 3.03 seconds = 41.65 MB/sec<br>[root@mythtv ~]# hdparm -Tt /dev/sdc<br>
<br>/dev/sdc:<br> Timing cached reads: 1416 MB in 2.00 seconds = 707.76 MB/sec<br> Timing buffered disk reads: 96 MB in 3.48 seconds = 27.59 MB/sec<br>[root@mythtv ~]#<br><br><br> </div></div><br>