I started using OneSwarm shortly after release yesterday and have been evangelizing and trying to build a sizable mesh. During this, I've noticed a few issues which I think you should be made aware of. Some of them may qualify as bugs, some may be known issues that don't have ready solutions.
1. Hashing performance
The data shares I set in my watch list upon installation total 1959GB. While I didn't expect it to has quickly, after 24 hours had passed hashing still had not been completed when running on a system with quad core processor running at 3.6GHz with 8GB of RAM. It appears to me that hashing performance is CPU bound and could be significantly improved by threading the hashing operation so that multi-core CPUs could be properly utilized.
2. As a corollary to the first issue, hashing randomly stops after some time. Exiting OneSwarm and restarting causes hashing to begin again without issue, but this recurs several times. I believe this may related to performance issues with hashing and perhaps performance with internal data structures used to store information about the swarms.
3. Remote Interface
Requests to the remote interface don't take precedence in the application over using outgoing bandwidth for transferring data. This is a flaw, because if you are not throttling outgoing bandwidth (and you shouldn't have to) you are unable to remotely control the application to change any settings regarding bandwidth usage or anything else. It simply times out, even if the host has reasonable pings (I was able to ping from an outside line at average of 30ms but could not connect to the remote interface). For the moment the workaround has been to implement QoS internally on my network and to give precedence for HTTPS traffic going to the IP of the box running OneSwarm, this seems to have alleviated the issue.
4. Scalability
As more nodes/friends are added to my mesh and I add more data to my shares, performance issues and general issues become more frequent and more likely to be catastrophic, requiring me to restart OneSwarm for everything to work properly once again. I've received errors about tracker failure after I had more than 3000 swarms loaded, and as mentioned before severe performance issues with hashing. As more nodes are added, it can't seem to keep track of connection states either, sometimes seeing LAN nodes as disconnected, even though there is gobs of bandwidth available between them (2GbE on both nodes). Performing a Force Connect on LAN nodes that show as disconnected (when they should not be) does fix this issue, but it is troublesome.
5. Friend adding
I've seen multiple instances in which either the Gtalk or LAN friend adding doesn't work properly, or even after adding a friend (trying more than once even) it doesn't believe that the person accepted and keeps them grayed out. In all instances, however, it can be worked around by doing a manual key exchange and adding that way. These problems seem to occur more frequently with the more friends that you have added. In addition if a single user has multiple nodes on their network that are Internet accessible running OneSwarm, the Gtalk bot service appears to get severely confused if you try to connect to your Gtalk account on both. The workaround for the moment to make Gtalk adds work is to have a separate Gtalk account for each node internally, luckily this doesn't affect the LAN adding and doing a manual key exchange still works fine of course.
All in all, I'm quite optimistic about the future of OneSwarm and find it very interesting. It does seem to perform well under smaller loads and I understand that with the size of data that I'm sharing from the nodes and the type of setup I'm using is probably not what was conceived as the norm during development. Hopefully as the project matures some of the above items will be addressed, especially with better threading for the application which I believe may solve many of the scalability issues.