impala-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Michael Ho (Code Review)" <ger...@cloudera.org>
Subject [Impala-ASF-CR] IMPALA-3946: fix MemPool integrity issues with empty chunks
Date Wed, 10 Aug 2016 02:00:59 GMT
Michael Ho has posted comments on this change.

Change subject: IMPALA-3946: fix MemPool integrity issues with empty chunks
......................................................................


Patch Set 1:

(4 comments)

http://gerrit.cloudera.org:8080/#/c/3838/1/be/src/runtime/mem-pool-test.cc
File be/src/runtime/mem-pool-test.cc:

PS1, Line 435: Empty chunk
May be I misunderstood it but I think you meant the chunk from src isn't transferred. Whether
the chunk is transferred should have nothing to do whether the chunk is empty or not, right
?


http://gerrit.cloudera.org:8080/#/c/3838/1/be/src/runtime/mem-pool.cc
File be/src/runtime/mem-pool.cc:

PS1, Line 105: int first_free_idx = 0;
IMHO, It may be slightly clearer to make the assignment of this variable more explicit:

if (UNLIKELY(current_chunk_idx_ == -1)) {
    first_free_idx = 0;
} else {
    DCHECK_GE(current_chunk_idx, 0);
    first_free_idx = current_chunk_idx_ + (chunks_[current_chunk_idx_]  > 0);
    // Always start at current_chunk_idx + 1 as we know the current chunk cannot fit.
    for (int idx = current_chunk_idx_ + 1; idx < chunks_.size(); ++idx) {
     ....
    }
}

It would be great to also document that the reason there can be a list of free chunks after
the current chunk is a result of calling Clear() in the past. That always confuses me when
I read this function without reading other functions at the same time.


PS1, Line 215: false
Is there a reason why this cannot be !keep_current || src->GetFreeOffset() > 0 ?


PS1, Line 260:  if (current_chunk_empty)
Can we keep the stricter check we had before if we modify line 215 ?


-- 
To view, visit http://gerrit.cloudera.org:8080/3838
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-MessageType: comment
Gerrit-Change-Id: I03ad12e5b2b63cbb55e5c52562416d73a4bd9346
Gerrit-PatchSet: 1
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Tim Armstrong <tarmstrong@cloudera.com>
Gerrit-Reviewer: Michael Ho
Gerrit-Reviewer: Michael Ho <kwho@cloudera.com>
Gerrit-Reviewer: Tim Armstrong <tarmstrong@cloudera.com>
Gerrit-HasComments: Yes

Mime
View raw message