Function Clause Error in yz_entropy [JIRA: RIAK-2068]

[rzezeski]

There seems to be a missing function head in yz_entropy when
iterating tree data. It looks like it can't deal with request
timeouts. It shouldn't be the end of the world if the tree builder
crashes because of this error as it will just be retried later but
might me good to retry the request or fail with a better message
(remember it's okay to fail in Erlang).

Here is a copy of the message from basho/riak_kv#854. The last message
is the issue. I do not believe any of the previous messages are
related.

2014-02-21 17:19:12.289 [error] <0.781.0> gen_server <0.781.0> terminated with reason: bad argument in call to erlang:byte_size({r_object,<<"IPDB">>,<<65,1,1,0>>,[{r_content,{dict,5,16,16,8,80,48,{[],[],[],[],[],[],[],[],[],...},...},...}],...}) in riak_kv_index_hashtree:maybe_throttle_build/4 line 460
2014-02-21 17:19:12.289 [error] <0.781.0> CRASH REPORT Process <0.781.0> with 0 neighbours exited with reason: bad argument in call to erlang:byte_size({r_object,<<"IPDB">>,<<65,1,1,0>>,[{r_content,{dict,5,16,16,8,80,48,{[],[],[],[],[],[],[],[],[],...},...},...}],...}) in riak_kv_index_hashtree:maybe_throttle_build/4 line 460 in gen_server:terminate/6 line 744
2014-02-21 17:19:12.289 [error] <0.773.0> Supervisor {<0.773.0>,poolboy_sup} had child riak_core_vnode_worker started with {riak_core_vnode_worker,start_link,undefined} at <0.781.0> exit with reason bad argument in call to erlang:byte_size({r_object,<<"IPDB">>,<<65,1,1,0>>,[{r_content,{dict,5,16,16,8,80,48,{[],[],[],[],[],[],[],[],[],...},...},...}],...}) in riak_kv_index_hashtree:maybe_throttle_build/4 line 460 in context child_terminated
2014-02-21 17:20:02.239 [error] emulator Error in process <0.21517.375> on node 'riak@altostratus.fabric' with exit value: {function_clause,[{yz_entropy,iterate_entropy_data,[<<3 bytes>>,[{continuation,none},{limit,100},{partition,6}],#Fun<yz_index_hashtree.5.14605823>,{error,{error,req_timedout}}],[{file,"src/yz_entropy.erl"},{line,44}]},{yz_index_hashtree,'-fold_keys/2-lc$^0/1-0-',3,[{...

[DSomogyi]

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