[tahoe-dev] Observations on Tahoe performance

[Francois Deppierraz]

Hi Shawn,

Shawn Willden wrote:

> The first observation is that when uploading small files it is very hard to 
> keep the upstream pipe full, regardless of my configuration.  My upstream 
> connection is only about 400 kbps, but I can't sustain any more than about 
> 200 kbps usage regardless of whether I'm using a local node that goes through 
> a helper, direct to the helper, or a local node without the helper.  Of 
> course, not using the helper produces the worst effective throughput, because 
> the uploaded data volume stays about the same, but the data is FEC-expanded.

This is probably because Tahoe doesn't use a windowing protocol which
makes it especially sensitive to the latency between nodes.

You should have a look at Brian's description in bug #397.

François

http://allmydata.org/trac/tahoe/ticket/397