[mythtv-users] Fwd: Pixelation/Bad Recordings HDHR Prime -- I am at my wits end

[Joseph Fry]

>>>> I have a few routes I can go here; first, I could use a separate spindle
>>>> for
>>>> just my recordings (right now it is being shared with a Windows Server
>>>> data
>>>> share that sees fairly little i/o). Second, I could pop in a 60gb SSD I
>>>> have
>>>> laying around and write some recordings to that to see if it makes a
>>>> difference.
>>>>
>>>> Any suggestions?
>>
>>
>> You can also use HDHomerun commands to record and save the live streams
>> (that play ok in VLC), and then play them direct from disc, which might be a
>> quick useful test of disc I/O.  Their manual is likely to be found on their
>> server.
>>
>> Can also save from mythweb to disc, and play using VLC for a 2nd view. Even
>> play these files on another machine?
>>
>>
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>
> My backend is running as a VM, so I can view it through the console,
> but I don't have any sound.  The easiest and most prevalent signs of
> this issue are with the audio, so I don't think using VLC on it will
> work very well.

Good point.

> My file system is already EXT4 and I didn't use any special formatting
> that I am aware of, I just installed MythBuntu and let it do the rest.

If you installed a recent OS, then most likely it aligned your sectors
properly... though if your using a virtual disk, I can't be sure that
ESX did.

> I only have one SATA controller and I do not know of a way to allow
> the VM to access it directly (unless it is a SAN, which it isn't).
> The SCSI controller is showing up as "LSI Logic Parallel" and it did
> this automatically.

Typically you can pass some devices through to a VM, meaning the host
doesn't access the device itself, or virtualize it for the VM....
instead the VM uses the device directly using the actual device
drivers.  I know you can do this with some devices, as folks have used
it in the past to access PCIe tuners... again I have never used ESX,
so I don't know how it's done.  If you only have one SATA controller,
then it's not likely to be any help to you anyway.

A quick bit of research says that ESX calls these RDM (raw device
mappings), and this thread says it can be done with a sata disk:
http://www.vm-help.com/forum/viewtopic.php?f=14&t=1025.  Once set up,
ESX would essentially ignore your recording drives, instead, the
entire physical disk would be assigned to the VM to be partitioned,
formatted, etc.  In other words, it would not be virtualized.

> I am not using RAID at all as ESXi does not recognize "fake
> raid"/software RAID built into the motherboard, from what I gather.

I wouldn't think that it would... and RAID is great but would add
another layer of complexity, so it's good that your not using it.

> Regarding "dynamic virtual disks" I assume you are asking if they are
> thin or thick provisioned?  They are thick provisioned.

I don't use ESX, but with many VM's I have used int he past, you can
create "virtual" disks, or assign a physical disk to the system.  A
virtual disk appears as a disk to the VM, but in reality is is one or
more files on the host's filesystem that are either a fixed size
(thick) or allowed to grow dynamically to some set maximum (thin).  I
would attach a physical disk to the backend VM if possible rather than
creating a virtual disk.

> I have dedicated and entire spindle to Myth's recordings volume, and
> in the meantime I will try to record from Myth to a CIFS share on my
> desktop to see how that works, which was a suggestion provided to me
> offline.

I don't know what your Windows Server is doing for you... but if it
were me, I would drop ESX and install ubuntu on the server, then use
virtualbox, or vmware workstation, or whatever to virtualize the
windows server.  This way the Backend would have full access to the
hardware, and you could actually use it as a frontend too if you
desired (I do)... but you would still be able to run virtual machines
for other servers you needed.