On Tue, May 19, 2015 at 1:34 AM, Rob Landley <[email protected]> wrote: > On Mon, May 18, 2015 at 2:01 PM, Bill Speirs <[email protected]> wrote: >> My goal is to provide Amazon S3 or Google Cloud Storage as a block >> device. I would like to leverage the libraries that exist for both >> systems by servicing requests via a user space program. >> ... ndb seems like a bit of a Rube Goldberg solution. > > I wrote the busybox and toybox nbd clients, and have a todo list item > to write an nbd server for toybox. I believe there's also an nbd > server in qemu. I haven't found any decent documentation on the > protocol yet, but what specifically makes you describe it as rube > goldberg?
My understanding of using nbd is: - Write an ndb-server that is essentially a gateway between nbd and S3/Google. For each nbd request, I translate it into the appropriate S3/Google request and respond appropriately. - I'd run the above server on the machine on some port. - I'd run a client on the same server using 127.0.0.1 and the above port, providing the nbd block device. - Go drink a beer as I rack up a huge bill with Amazon or Google Seems a bit much to run a client & server on the same machine with socket overhead, etc. In looking at the code for your nbd-client (https://github.com/landley/toybox/blob/master/toys/other/nbd_client.c) I'm wondering if I couldn't just set a pipe instead of a socket in the ioctl(nbd, NBD_SET_SOCK, sock) step, then have the same proc (or fork) listening on the pipe so it's all in a single process/codebase. Thoughts on this approach? That said, clearly my bottleneck in all of this will be the communication with S3/Google, and using something like dm-cache would make it appear fast for most requests. So maybe my Rube Goldberg comment was too over-the-top. Thank you for the pointers and the feedback! Bill- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
