Re: [ANN] Dynamic object interfaces in RADOS with Lua

[Noah Watkins <jayhawk@...>]

On Tue, Oct 29, 2013 at 11:54 AM, Javier Guerra Giraldez <javier@guerrag.com> wrote:

On Tue, Oct 29, 2013 at 1:06 PM, Noah Watkins <jayhawk@cs.ucsc.edu> wrote:
> I'd like to announce a project that you may find interesting that embeds the
> Lua VM (currently only LuaJIT) in the Ceph distributed object storage system

very nice!

just a few questions:

1) i've found the lua-rados client binding lib docs, but not about the
API available to the embedded scripts.  is that documented somewhere?
if not docs, how about the source code?

Yeh, the embedded scripts don't yet have any proper documentation. Here is a link to where the environment gets setup:

https://github.com/ceph/ceph/blob/cls-lua/src/cls/lua/cls_lua.cc#L375

https://github.com/ceph/ceph/blob/cls-lua/src/cls/lua/cls_lua.cc#L406

 

2) what's the scope and persistance of registered handler scripts?
IOW: if i run a tool that just registers a few handlers, then every
other client will be able to call those handlers?  if so, does the
registration survives OSD reboots?  what about new OSDs?

Currently the scripts are sent along with each request, so the scope is a client and there is no persistence. I think this is going to be the focus of our next steps, namely to use a single VM instance (rather than one-per-request right now), as well as persisting the scripts, although I'm not sure what the scoping will look like in that case.