Block Level vs File Level Storage

[Taddeusz]

I've asked this before some time ago without a definitive answer. I'm hoping Jeff can chime in since he would have the best knowledge of how SageTV saves recordings.

Since SageTV is now open source I'm still wondering if there is an advantage to using block level storage vs file level storage for recording directories? In other words using paths to physical disks or iSCSI devices using the native file system (e.g. NTFS etc) vs using local or network Windows/SMB shares.

Just as an example I know when working with Microsoft SQL Server backups you are limited to full backups when using file level storage. Only when you backup to block level storage will it allow you to do incremental backups.

I know SageTV will record to local or network shares but I'm wondering if there is any performance or other benefit to using a physical disk path?

[Narflex]

I'm not really sure I understand what you're asking here. When you say file vs. block storage....I'd assume you were referring to not even using a standard filesystem and just writing to the block device (HDD) directly and managing all of our own information around what blocks contains what data.

But in what you're explaining; it seems like you're asking about using a local physical disk vs. using network storage. For that; it's really all performance related. A local physical disk will pretty much always be faster than network storage...but if you have enough bandwidth and your network storage is fast enough; then everything will likely work just fine that way as well. You also never need to worry about the case of the filesystem actually being offline (although SageTV handles that very well).

[Taddeusz]

Originally Posted by Narflex

I'm not really sure I understand what you're asking here. When you say file vs. block storage....I'd assume you were referring to not even using a standard filesystem and just writing to the block device (HDD) directly and managing all of our own information around what blocks contains what data.

But in what you're explaining; it seems like you're asking about using a local physical disk vs. using network storage. For that; it's really all performance related. A local physical disk will pretty much always be faster than network storage...but if you have enough bandwidth and your network storage is fast enough; then everything will likely work just fine that way as well. You also never need to worry about the case of the filesystem actually being offline (although SageTV handles that very well).

Thank you. I was just curious if there was anything in the code, like with SQL Server backups, that gives a notable advantage to directly using a file system vs a share.

[Narflex]

Originally Posted by Taddeusz

Thank you. I was just curious if there was anything in the code, like with SQL Server backups, that gives a notable advantage to directly using a file system vs a share.

No, nothing special. We just treat everything as a file and let the operating system do the other abstractions (only special case is relating to detecting if a folder is offline; we do that a little differently for network shares).

[wayner]

I have always preferred using UNC paths for media files in Sage as it makes it easy if you want to change hard drives - you just change the share. And it especially works well if you are changing a share from an entire drive to just a path on a drive - thanks to larger hard drives I no longer need an entire drive to hold music.

So my media libraries are in folders like:
\\\myserver\Videos
\\myserver\Movies
\\myserver\Music

rather than F:\, G:\, H:\