Optimum Timeshift buffer settings for four+ tuners?

[Benoire]

Hi,

I recall a discussion (not sure if it was Argus or 4TR) about the timeshift buffers and what they actually meant in terms of the number of buffers and size. Are the buffers allocated per card or general? Any optimum settings for 4 tuners or more?

Thanks,

Chris

[andrewNZ]

I think buffers are per timeshifing instance. So if you have 1 card and 4 clients streaming you'll have 4 sets of files.

[Benoire]

so ideally you want to match the number of buffers by tuners, assuming you've set it to one channel tune per mux? So in my case, I have four tuners and two clients and as I only ever set mdapi to decode one channel per tuner 4 buffer files at say 8gb each for an hour hold with HD should be sufficient?

[andrewNZ]

...You've lost me.

To clarify what I meant (and I may be wrong). One client timeshifting will create one set of files as per the settings (4@750MB). Two clients timeshifting will create two sets of files (8@750MB).

I think the reason for multiple files is to get around the FAT32 file size limit of 4GB per file. As far as I know there's no relation to the number of tuners.

[Benoire]

Right so (Dot-i it would be great to have some thought from you on this) a client will simply create a 'set' of timeshift files relating to what it is doing? as you've said if I set 4 files at 3Gb each then each client would create (if required?) 4 timeshift buffers with a total size of 12Gb before overwriting stored info? So is the full size timeshift buffer created at once or does it grow as needed, i.e. does it create a single 3gb file first or a single file slowly changing in size until it exceeds 3gb and then it creates timeshift file 2 for that client? OR does it create all 4 up front?

[Caesium]

a single file slowly changing in size until it exceeds 3gb and then it creates timeshift file 2 for that client

this one

[Benoire]

so if two clients are watching the same channel it would create 2 timeshift buffer(s) relating to that stream, the same is if two clients where watching two different channels? In which case is it better to have 1 big file or many small files? i.e. assume one client; 1 8gb file or 2 4gb files?

[Caesium]

Actually having just tested this, it created my first two files at fullsize right away. I have 10 defined files per tuner, so don't know why it made two in particular

But, yes, if two clients watch the same (or different) channel it does make two sets of timeshift files.

I don't think it makes any real difference whether you have 10x400MB or 1x4GB file. As previously said, the only reason for splitting it up is for filesystem size limits which these days should be a thing of the past anyway, unless you're still using FAT32 (why?!)

[Benoire]

Is any one able to drop it down to a single file per client? I tried changing it to 1 8GB file and it will only allow me to go as low as 2 files...

[Caesium]

Nope, two here too, never noticed that before.