[KUDU-1590] cache-test failing on my laptop

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.0.0
• Fix Version/s: 1.0.0
• Component/s: test
• Assignee: Todd Lipcon
• Reporter: Adar Dembo
• Created: 03/Sep/16 02:11
• Updated: 07/Sep/16 00:22
• Resolved: 07/Sep/16 00:22

Description

Here's the failure:

[ RUN      ] CacheTypes/CacheTest.EvictionPolicy/0
/home/adar/Source/kudu/src/kudu/util/cache-test.cc:198: Failure
Value of: Lookup(200)
  Actual: 201
Expected: -1
I0902 19:07:59.004560 25663 test_util.cc:78] -----------------------------------------------
I0902 19:07:59.004580 25663 test_util.cc:79] Had fatal failures, leaving test files at /tmp/kudutest-1000/cache-test.CacheTypes_CacheTest.EvictionPolicy_0.1472868478986786-25663
[  FAILED  ] CacheTypes/CacheTest.EvictionPolicy/0, where GetParam() = 0 (6 ms)

I suspect this is due to commit bfb6f23, but I don't know how. Amusingly, CacheTest.EvictionPolicy/1 (for NVM_CACHE) is passing.

Here's what I know:

• I was working on upgrading to LLVM 3.9 when I noticed this. I rolled back to LLVM 3.8 and the problem persisted, so I suspect it has nothing to do with the LLVM upgrade.
• I can't repro it on ve0518 normally.
• But if I replace the call to base::NumCPUs() in cache.cc with 8 (the number of cores on my laptop), it reproduces in the exact same way on ve0518.