Optimal block size for streaming video files?

[Lachlan Donald]

Hi, I'm trying to figure out the optimal block size to use with streaming video files hosted in s3ql / amazon s3. The files are around 800Mb-1.2Gb and are generally streamed sequentially. I'm presently using a 10Mb blocksize and trying to decide whether it's worth increasing that (I presume I'd have to copy to a new filesystem). 

Also, are the blocks for a file fetched in parallel or sequentially? Watching the logs makes me thing sequentially, but hard to tell. 

[Nikolaus Rath]

On Jan 02 2016, Lachlan Donald <lac...@ljd.cc> wrote:
> Hi, I'm trying to figure out the optimal block size to use with streaming
> video files hosted in s3ql / amazon s3. The files are around 800Mb-1.2Gb
> and are generally streamed sequentially. I'm presently using a 10Mb
> blocksize and trying to decide whether it's worth increasing that (I
> presume I'd have to copy to a new filesystem).

I don't think you would gain anything by changing the block size. What
do you expect from the "optimum"?

> Also, are the blocks for a file fetched in parallel or sequentially?

They can be fetched in parallel, but fetching is only initiated when an
application tries to read the data. And your movie player is probably
just accessing one block after the other.


https://bitbucket.org/nikratio/s3ql/issues/186/pre-fetch-data would
probably be interesting for you.


Best,
-Nikolaus

--
GPG encrypted emails preferred. Key id: 0xD113FCAC3C4E599F
Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F

»Time flies like an arrow, fruit flies like a Banana.«