On Fri, Jan 11, 2013 at 10:32 AM, Kristof Provost <kristof@xxxxxxxxxx> wrote: > > On 2013-01-10 16:09:49 (-0500), Simon <turner25@xxxxxxxxx> wrote: > > Firstly, I was wondering if it would be possible to implement the > > filesystem entirely as a kernel module. I would need TCP/UDP sockets. > > I > > think this is really not the recommended approach, but an advantage I > > see > > is it could be used to mount the root filesystem before calling init > > (that > > would be before user-space exists, right?). On the other hand, > > separating > > the work to have a program/daemon in user-space do the communication and > > processing would allow me to write that part in C++ (which I personally > > prefer). > > It's certainly possible to implement a network file system entirely in > kernel space. That's where NFS is implemented. > If you *really* care about performance it's pretty much the only way to > go. If you don't you should keep as much as possible in user space. > > In either case I'd recommend you start your development on top of fuse > though. That means you can implement all new code in user space, in > whatever language you prefer. It'll be much easier to debug in any case. > Think of it as a fast prototype, to validate your protocol. Hi Kristof, thanks for your reply. On my personnal projects, when starting from scratch, I usually set the goal to "refuse optimization" the code or the goal to "write inefficient code". This is mostly a psychological barrier to avoid premature optimization, which I am prone to. However, efficiency is a goal for the later stages and so writing the whole thing in kernel space from the start might be a good idea (less stuff to rewrite or to "fit in"). About using FUSE. I have to say your arguments for its use are compelling. However, one of my hidden goals is to learn and practice kernel programming and if I'd use fuse, I'd be constrained to "fuse programming" which is also restricted to filesystems. The day I want to build something else I would have to start from square one with kernel programming. Also, another project I have in mind after this one is to implement the same concept, but using a block device instead (I think this comes very close to what iSCSI does). It would enable the use of RAID or LVM on top of that networked block device. I don't think this will be more efficient than my current project (specially for use on the internet), but it might be useful in other ways (for backups perhaps, or a raid mirror of local device with networked device tuned with --write-mostly and --write-behind). At least, mdadm can be used to handle disconnects/failures, to resync the devices, to manage what remote hosts are used. Anyway, this one is still a very foggy idea in my mind; it has the word "perhaps" stamped in red across it! ;) I'll weight the pros and cons for using fuse when I feel ready to start development. Thanks again, Simon _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
