Henry Robinson has posted comments on this change.

Change subject: IMPALA-3610: Account for memory used by filters in the 
coordinator
......................................................................


Patch Set 2:

(3 comments)

http://gerrit.cloudera.org:8080/#/c/3618/2/be/src/runtime/coordinator.cc
File be/src/runtime/coordinator.cc:

PS2, Line 2077: state->DiscardFilter(filter_mem_tracker_.get());
> Isn't this essentially a no-op, because an always_true_filter will always j
it's the latter. One partitioned filter provider might run out of memory and 
abort its filter construction, but would send a NULL filter to stop the 
coordinator waiting for it.


PS2, Line 2090: state->pending_count == 0
> Wouldn't this always be 0 for a broadcast join filter? Given that we always
You're right, good catch. This is always 0 at this point for a broadcast join. 
Better to track the number received explicitly rather than overloading what 
pending_count means for different filter types.


PS2, Line 2110:     for (const auto& target: state->targets) {
              :       // Don't publish the filter to targets that are in the 
same fragment as the join
              :       // that produced it.
              :       if (target.is_local) continue;
              :       
target_fragment_instance_idxs.insert(target.fragment_instance_idxs.begin(),
              :           target.fragment_instance_idxs.end());
              :     }
> Seems like state->targets is read only at this point, because it's set only
Are you worried that this is an expensive loop? Otherwise I think it's better 
to have something that's clearly correct (access shared state under lock) than 
to have an optimization that is correct, but not obviously so


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Gerrit-MessageType: comment
Gerrit-Change-Id: I3c52c8a1c2e79ef370c77bf264885fc859678d1b
Gerrit-PatchSet: 2
Gerrit-Project: Impala
Gerrit-Branch: cdh5-trunk
Gerrit-Owner: Henry Robinson <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Reviewer: Henry Robinson <[email protected]>
Gerrit-Reviewer: Mostafa Mokhtar <[email protected]>
Gerrit-Reviewer: Sailesh Mukil <[email protected]>
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