RFR: JDK-8221596: test/hotspot/jtreg/runtime/containers/docker/TestCPUSets.java failed with FileAlreadyExistsException

[Mikhailo Seledtsov]

Hi Jie, David,

I did a bit of digging:

    - @run driver ClassFileInstaller -jar whitebox.jar 
sun.hotspot.WhiteBox sun.hotspot.WhiteBox$WhiteBoxPermission
      is used in TestCPUSets.java, TestMemoryAwareness.java and 
TestMisc.java
      This instruction will generate whitebox.jar and place it in 
"current working jtreg directory", which is
      ./JTwork/scratch/

    - in order to be able to use the WhiteBox.jar from within the Docker 
container, it is copied
      to the "JTReg test classes" directory (defined by 
jdk.test.lib.utils.TEST_CLASSES)
      This Utils.TEST_CLASSES directory is mounted via --volume at 
docker-run-time, so that classes can be
      visible/usable/loadable from within the container.

    -  This Utils.TEST_CLASSES directory is unique for each test run:
       ./JTwork/classes/runtime/containers/docker/TestMisc.d/whitebox.jar
       
./JTwork/classes/runtime/containers/docker/TestMemoryAwareness.d/whitebox.jar
       ./JTwork/classes/runtime/containers/docker/TestCPUSets.d/whitebox.jar
       Hence, I do not see a possibility of file access clash among the 
different tests.

    - if tests are run concurrently (with -conc:X feature), each test 
gets their own scratch directory
      classes directories are also separated, as in non-concurrent case
      ./JTwork/scratch/1/whitebox.jar
      ./JTwork/scratch/0/whitebox.jar
      ./JTwork/scratch/2/whitebox.jar
      
./JTwork/classes/3/runtime/containers/docker/TestCPUSets.d/whitebox.jar
      ./JTwork/classes/4/runtime/containers/docker/TestMisc.d/whitebox.jar
      
./JTwork/classes/0/runtime/containers/docker/TestMemoryAwareness.d/whitebox.jar
      No file access clashes among tests either

    Is it possible that you did not clean out the directory from the 
previous run? For test execution, we recommend
    clearning JT* directories from the prior run before a new run (rm 
-Rf JT* or similar). This recommendation is not
    specific to Docker testing, it is a good practice in general for 
executing of jtreg tests.



Thank you,
Misha

On 3/28/19, 4:16 AM, David Holmes wrote:
> Hi Jie,
>
> On 28/03/2019 5:48 pm, Jie Fu wrote:
>> Hi David,
>>
>> Thanks for your review.
>>
>>>
>>> Normally to use WhiteBox a test specifies:
>>>
>>>  @run driver ClassFileInstaller sun.hotspot.WhiteBox
>> Yes, we do have it in 
>> test/hotspot/jtreg/runtime/containers/docker/TestCPUSets.java
>
> Okay I'm not understanding why Common is copying the WhiteBox classes 
> or where it is copying them to? If this is something to do with the 
> image shouldn't it be completely clean when the test is run - either 
> by deleting existing files or by ensuring a unique location to begin 
> with?
>
> Thanks,
> David
>
>> Best regard,
>> Jie
>>>
>>> Is there a reason this test can't use that?
>>>
>>> Thanks,
>>> David
>>> -----
>>