Adar Dembo has posted comments on this change.

Change subject: Add a simple benchmark to create 1M blocks and reopen LBM
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Patch Set 2: Code-Review+2

(1 comment)

Based on my understanding of mkfs block size choices, I think your assertion 
about sync_file_range and stable page writes is overly strong.

But the code is fine, so feel free to ignore and merge as is.

http://gerrit.cloudera.org:8080/#/c/8006/2/src/kudu/fs/log_block_manager-test.cc
File src/kudu/fs/log_block_manager-test.cc:

PS2, Line 797: In particular,
             :   // since we write such small blocks in this test, each block 
will likely
             :   // begin on the same 4KB page as the prior one we wrote, and 
due to the
             :   // "stable page writes" feature, each block will thus end up 
waiting
             :   // on the writeback of the prior one.
That's only true when the filesystem block size is less than 4K though, right? 
I don't know why many of our test machines wound up with 2K ext4 filesystems; 
4K is generally the default on ext4 (provided the fs isn't of a trivially small 
size).


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Gerrit-MessageType: comment
Gerrit-Change-Id: I5cc3547db7d8389c4e89ff9d4d3043b5f2fbe878
Gerrit-PatchSet: 2
Gerrit-Project: kudu
Gerrit-Branch: master
Gerrit-Owner: Todd Lipcon <[email protected]>
Gerrit-Reviewer: Adar Dembo <[email protected]>
Gerrit-Reviewer: Dan Burkert <[email protected]>
Gerrit-Reviewer: David Ribeiro Alves <[email protected]>
Gerrit-Reviewer: Hao Hao <[email protected]>
Gerrit-Reviewer: Kudu Jenkins
Gerrit-Reviewer: Todd Lipcon <[email protected]>
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