Disclaimer: I haven't done this myself, or even attempted to compile the code
below, but in hopes it makes your life a little easier...
Here's some Erlang that should allow you to abstract away the checks. Assuming
that you have a function named "real_map_fun" that takes a single Riak object
as
Thanks for the response. To handle not founds and tombstones I need this in
every map function?
map_something({error, notfound}, _, _) ->
[];
map_something(RiakObj, _, _) ->
Metadata = riak_object:get_metadata(RiakObj),
case dict:is_key(<<"X-Riak-Deleted">>, Metadata) of
true -
I'm sorry this went unanswered, Jeremy. Thanks for the follow up.
Your code needs to be able to handle notfound errors and tombstones[1]
regardless of ownership handoff. The coverage for the 2i or listkeys input will
be calculated up front, with the work distributed to a node where the key is
So I should expect {error, notfound} inputs to map jobs while ownership
handoff is in progress? Are the not found items actually unavailable during
handoff or is this just not found on the old node, but will be picked up by
the new node during the same mapreduce job?
--
Jeremy
On Thu, Feb 28, 20
Yesterday I added a new node to my cluster. During the time when ownership
handoff was happening (several hours of work) mapreduce map functions were
receiving {error, notfound} as inputs. My Erlang mapred functions weren't
designed to handle this. They hadn't encountered this before during normal
