[mythtv-users] OT? Hardware Differences
beww at beww.org
Thu Apr 13 17:36:17 UTC 2006
On Apr 13, 1989, at 11:25 AM, R. G. Newbury wrote:
> Brian Wood wrote:
>> On Apr 13, 1989, at 8:25 AM, R. G. Newbury wrote:
>>> This is a little offthread but it does affect my use of myth. And
>>> list has shown that it is a source of deep knownledge about linux.
>>> I have 2 exactly similar 40G hard drives: model IC35L040AVVN07-0.
>>> the same day, same order.
>>> Playing with hdparm I can set the master /dev/hda to use udma=5
>>> the -X69 parameter.
>>> The slave /dev/hdb will only do udma=2.
>>> As a result, although the cached read speeds are similar at about
>>> 730MB/s, the buffered read on hdb is 19.6MB.s versus 45 MB/s on hda
>>> The only difference I can see is that hdb reports:
>>> AdvancedPM=yes: unknown setting while hda reports AdvancedPM=yes:
>>> disabled (255), and attempting to set APM on hdb gives the following
>>> error: HDIO_DRIVE_CMD failed: Input/output error
>>> It appears that neither APM nor acoustic management features
>>> get changed/set when I use hdparm... Weird!
>>> I can get/set the other commands/switches on the drive so this is
>>> than a little weird.
>>> I want to move this drive to my mythbox and do the OS install
>>> onto it,
>>> and use the entirety of the present 120G for recording...But the
>>> throughput problem puts this plan in doubt. Any thoughts anyone.
>> Are you using an 80-conductor UDMA-type cable ?? You can get strange
>> results if you don't use one of these.
>> Have you tried swapping the drives and seeing if the "problem" drive
>> changes to the other one?
> Both drives are on the same 80 conductor cable IIRC and the problem
> drive has no OS, so 'swapping' them would be difficult to
> implement, or
> are you suggesting that it may be the position on the cable which
> is the
I suspect that you have a bad cable, moving the drives might help
confirm this. If you hard-strap the drives (ie: don't use cable
select) you may find that the problem follows the connector and not
More information about the mythtv-users