[mythtv-users] Howto prevent MythTV flushing/Syncing disk writes (LiveTV/Recordings) [ SOLVED ]

[Allan Stirling]

Albert Graham wrote:
> Allan Stirling wrote:
>> cal wrote:
>>   
>>> Allan Stirling wrote:
>>>     
>>>> When a slave backend is NFS mounted, as far as I understand
>>>> it, a recording won't appear on the server (and thus other
>>>> frontends) until it's synced.
>>>>
>>>> This means that mounted (non-streaming) live TV would not
>>>> work very well, which as far as I can tell was the original
>>>> intent of this piece of code.
>>>>       
>>> which is another good reason for a switch setting. Maybe when
>>> qt4 lands in trunk ... 
>>>     
>> No, it is not.
>>
>> Sorry - But myth has _way_ too many user-twiddleables
>> already. This confuses new users _and_ makes it harder to
>> optimize a system.
>>   
> Firstly, my suggestion is designed to solve a specific problem and not 
> really meant as an optimization.
>> The real way to do it could be to only fsync if you're in
>> this situation - To test (on startup):
>>
>> 1. SBE creates a file
>> 2. Sends a request to MBE to read file (repeated for a few
>> seconds)
>> 3. If MBE couldn't read the file, fsync()
>> 4. Test read again - If it now succeeds, set a fsyncneeded flag.
>>
>> If you're all on one box, none of this is required.
>>
>> Cheers,
>>
>> Allan.
>>   
> 
> But Allen,
> 
> The data does not need to be sync'd to be visible to.
> 
> My interpretation is that the slave backend (SBE) simply writes its 
> files via NFS to the "/recordings" directory and has nothing to do wth 
> the master  backend (MBE), so what you're saying is confusing!
> 
The MBE is just a point to test with which is guaranteed to
be available when a recording is happening.

Cheers,

Allan.