To allow using Terra Prime SSD as cache drive

[Substance]

I think this would make (Compact) Terra Prime SSD 8TB an automatic add-on (sale) to every existing and new Strato/Terra/Prime HDD system.

SETUP:

The cache drive option is available only if it is an add-on to a Terra/Prime HDD server. This is how it would work.

When adding a new Terra Prime SSD to an existing Strato/Terra/Prime HDD system, the setup screen prompts you to choose whether you want it as a storage expansion which is currently the only available option or you want to use it as a cache drive (my proposed new option).

The storage expansion option is basically how the kOS works now. So no changes there.

If you choose the cache drive option, your system uses the new Terra Prime SSD as your primary target download location. After finished viewing the recently downloaded movies (and while the Prime SSD is idle), it moves (transfers) these downloads to the larger Terra to free up its fast SSD storage. This can happen in the background overnight.

BENEFITS:

• The downloads occur at the highest possible speed (down to 4 mins per movie) up to 8TB worth of concurrent downloads in the queue.
• The cache drive automatically offloads its data to Terra or Terra HDD servers during system idle times.
• The fastest download speeds for the entirety of the system including the Terra/Prime HDD servers.
• This essentially makes the Terra Prime 88TB + Terra Prime SSD 8TB combo the best of both worlds (Largest storage plus fastest downloads).
• No hardware changes necessary. All of this can be done in software.

DRAWBACKS:

• Terra Prime SSD 8TB is a temporary storage in cache drive mode so it doesn’t expand the aggregate system storage size.
• Terra/Prime HDD used as the main storage would limit the system to maximum 10 simultaneous playback streams.
• It is an expensive add-on to enhance download speeds but a lot less expensive than an equivalent size system with all SSD servers.
• Could potentially hurt Terra Prime SSD 31TB sales but homes with 10+ zones would still favor Terra Prime SSD 31TB Servers.
• It could be difficult to detect/predict system idle times for transfers. The user might try to initiate playback while the file is in transfer. (The cache drive should hold off deleting the data until a duplicate is created on the Terra/Prime HDD).

OTHER POSSIBILITIES:

• A hybrid option could allow user to choose the dedicated cache drive space and use the remainder as storage expansion to the system. Ex: 2TB Cache drive/6TB storage expansion. I doubt it is very common to have 8 TB worth of concurrent downloads in one queue. At least it won’t happen often. I think 1TB or 2TB cache drive size is more than plenty.
• A smart hybrid option could dynamically adjust cache drive size based on use. Realistically, the storage expansion is needed only when the Terra HDD is full.
• A less expensive (Compact) Terra Prime SSD with 2TB could be offered for those who are interested in its cache drive ability only.
• A full size Terra Prime HDD/SSD hybrid server with 3x 22TB HDD+1x 8TB SSD for a 66TB to 86TB total system size depending on assigned cache size (min. 2TB, max. 8TB) could be easily put together with the existing Terra Prime HDD logicboard.
• Next Gen. Terra (Prime II?) server with 4xHDD bays plus 1x m.2 slot on the logic board for fast SSD cache drive.

 

[baltz]

I made a similar post over on the new product thread for the Terra prime, but I think you're making it more complicated than it needs to be.

There's no reason to have to give up the SSD as available storage. Once the slower storage is full, the SSD could still be used as storage.

The store will automatically download to the fastest device first, which is what we want. The only thing that would need added would be for the system to automatically move content from the fastest storage to the slowest storage when the system is idle. I think this would achieve the desired result without too much added complication.

I thought about it more after I posted on the other thread, and it wouldn't have to be exclusive to the SSD models. For example, someone might have a Strato S and a Terra. In that case, they might want to automatically move content from the Terra to the Strato S to always achieve ~800 mbps downloads on the Terra compared to ~200mbps on the Strato.

As you mentioned, there are concurrent stream limits, so there would probably need to be some configuration settings for the user.

 

[baltz]

Also, I hadn't considered the idea of a hybrid Terra, but that's a cool idea.

I could see 3x22TB HDDs and 1x8TB SSD (74TB total). It could download to the SSD first, and then move content to the 22TB drives when idle.

 

[Substance]

I made a similar post over on the new product thread for the Terra prime, but I think you're making it more complicated than it needs to be.

There's no reason to have to give up the SSD as available storage. Once the slower storage is full, the SSD could still be used as storage.

The store will automatically download to the fastest device first, which is what we want. The only thing that would need added would be for the system to automatically move content from the fastest storage to the slowest storage when the system is idle. I think this would achieve the desired result without too much added complication.

I thought about it more after I posted on the other thread, and it wouldn't have to be exclusive to the SSD models. For example, someone might have a Strato S and a Terra. In that case, they might want to automatically move content from the Terra to the Strato S to always achieve ~800 mbps downloads on the Terra compared to ~200mbps on the Strato.

As you mentioned, there are concurrent stream limits, so there would probably need to be some configuration settings for the user.

I replied to Tayloe and suggested SSD cache when the new products were introduced. I can’t see my posts anymore for some reason.

Assigning dedicated cache space has advantages. If the user wanted to watch that exact movie which the system is transferring, it will cause issues as none of the servers have the complete file. Dedicated cache space would hold duplicates of the files being transferred.

 

[Substance]

This idea just appeared in my head. The cache drive can be implemented even simpler than I thought.

Assume a system with a Terra Prime HDD and a (Compact) Terra Prime SSD.

When a purchase is made on the K store, it would create two download queues for the same movies. One for the Terra Prime SSD and another for the Terra Prime HDD (in the respective order). The Prime SSD would complete downloads in a short time then The Prime HDD would work on downloading the same files from the K Store rather than transferring in the local network. As the Terra HDD completes downloads the Terra Prime SSD would move those movies to trash. So these download and delete commands could all come from the store with no change to the current kOS. There is no need for a dedicated cache space either because the Prime SSD would always keep the files until the other Terra completes the downloads.

 

[Substance]

As you mentioned, there are concurrent stream limits, so there would probably need to be some configuration settings for the user.

I am sure K would be happy to sell you a second Terra Prime SSD if you need more cache headroom

 

[DieZwei]

Also, I hadn't considered the idea of a hybrid Terra, but that's a cool idea.

I could see 3x22TB HDDs and 1x8TB SSD (74TB total). It could download to the SSD first, and then move content to the 22TB drives when idle.

That´s what my data NAS is doing for years now.
Actually, a small 1TB M2 SSD would be sufficient for that.

 

[Substance]

That´s what my data NAS is doing for years now.
Actually, a small 1TB M2 SSD would be sufficient for that.

Next Gen. Terra definitely needs at least one m.2 slot on its logic board for this. It is a waste to lose the 3.5" bay for the cache drive. They could technically use the existing USB3.0 header on the logic board which should be similar to m.2 speeds (PCIe x4). It could even be an external add-on device. There is already a USB3.0 socket on the back of the server.