We should have a mechanism for storing sessions clientside but this is a speed issue not a scalability issues. Storing sessions in encrypted cookies makes a each request 1-2ms faster by trading bandhwidth (required to communicate the session in cookie) with file IO (required to locate and access the session in a file).
Scalability-wise sessions in files do not present a problem as long as one uses a load balancer with support with sticky sessions. On common problem arises when there are too many session files in the same folder (the os becomes slow accessing the folder). This problem has been solved in trunk last week by creating a sub-folder tree structure for the session folder. Session in files some advantages of sessions in cookies: they can contain more data. They can be controller server-side (checked, deleted, modified). They can be locked to force per-user serialization of form processing(default in web2py). Bottom line: current sessions are not a scalability issue but it would be nice to have the option of sessions in signed cookies. It is not difficult to do and we have it by the end of the year. This will be a major speed up for system that do not have a filesystem and currently require storing sessions on datastore, like on GAE. Massimo On Dec 1, 10:31 am, VP <vtp2...@gmail.com> wrote: > This is an example -- I think -- where web2py still needs to be proven > in terms of scalability. > > Yes, sessions can be stored in database, turned off in specific > functions, and regularly deleted. But I still think that there > should be a better systematic way of handling sessions in heavy > applications. I think the current set up is not effective when you > have large volume of users, which suddenly builds up many sessions. > > Small things like this don't matter much until things get large > scaled. > > === > > To take web2py to the next level, I think Massimo might need to lay > out milestones or visions to be achieved in future releases of > web2py. > > On Nov 30, 6:07 pm, Stef Mientki <stef.mien...@gmail.com> wrote: > > > On 30-11-2010 21:08, VP wrote:> I think .NET and web2py are not > > competitors. They are different ball > > > games. When things scale large, everything is important. A small > > > design issue might be magnified. I don't think web2py is proven yet, > > > in terms of scalability. What web2py needs is at least one real > > > example to show that it is scalable and what are the limits at the > > > extreme. > > > I'm not sure were session files are used for, > > but isn't file access much slower than database access ? > > > Can session files be turned of ? > > > cheers, > > Stef > >
