RFR: 8273438: Enable parallelism in vmTestbase/metaspace/stressHierarchy tests

[Aleksey Shipilev]

Current `vmTestbase/metaspace/stressHierarchy` tests (part of vmTestbase_vm_metaspace suite) contains about 15 tests, each running exclusively. There seem to be no reason to run them exclusively, though: they complete in reasonable time, are single-threaded, and consume the usual amount of memory. There is no evidence in JBS that they ever timed out without a reason, and their history unfortunately predates OpenJDK to see why they were not concurrent from day one.

We should consider enabling parallelism for `vmTestbase/metaspace/stressHierarchy` and get improved test performance. Currently it is blocked by `TEST.properties` with `exclusiveAccess.dirs` directives in them. 

Note there are other exclusive tests in `vmTestbase_vm_metaspace`, but those seem to be the hard stress tests: pushing GC to the limits, or doing many threads, etc.

Motivational test time improvements below.

Before:


$ time CONF=linux-x86_64-server-fastdebug make run-test TEST=vmTestbase_vm_metaspace | ts -s
...
00:24:53 ==============================
00:24:53 Test summary
00:24:53 ==============================
00:24:53    TEST                                              TOTAL  PASS  FAIL ERROR   
00:24:53    jtreg:test/hotspot/jtreg:vmTestbase_vm_metaspace     25    25     0     0   
00:24:53 ==============================
00:24:53 TEST SUCCESS
00:24:53 
00:24:53 Finished building target 'run-test' in configuration 'linux-x86_64-server-fastdebug'

real	24m53.389s
user	53m2.029s
sys	1m1.849s


After:


$ time CONF=linux-x86_64-server-fastdebug make run-test TEST=vmTestbase_vm_metaspace | ts -s
...
00:04:04 ==============================
00:04:04 Test summary
00:04:04 ==============================
00:04:04    TEST                                              TOTAL  PASS  FAIL ERROR   
00:04:04    jtreg:test/hotspot/jtreg:vmTestbase_vm_metaspace     25    25     0     0   
00:04:04 ==============================
00:04:04 TEST SUCCESS
00:04:04 
00:04:04 Finished building target 'run-test' in configuration 'linux-x86_64-server-fastdebug'

real	4m4.574s
user	56m10.582s
sys	1m4.725s

-------------

Commit messages:
 - Remove TEST.properties

Changes: https://git.openjdk.java.net/jdk/pull/5391/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5391&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8273438
  Stats: 15 lines in 15 files changed: 0 ins; 15 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5391.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5391/head:pull/5391

PR: https://git.openjdk.java.net/jdk/pull/5391