RFR: 8253411: [BACKOUT] [REDO] G1 incorrectly limiting young gen size when using the reserve can result in repeated full gcs

[Thomas Schatzl]

Hi all,

  can I have some reviews for this change that reverts commit fa30241ddbbe953b61526bc3c44784198acdd801.

Fix some merge error in this hunk:

>From https://github.com/openjdk/jdk/commit/3570f5a9,  8252041: G1: Fix incorrect uses of HeapRegionManager::max_length
, the method "max_expandable_regions()" has been changed to "max_regions()" so the first use of it in the hunk

@@ -108,11 +107,14 @@ void G1Policy::init(G1CollectedHeap* g1h, G1CollectionSet* collection_set) {

+   if (!use_adaptive_young_list_length()) {
+    _young_list_fixed_length = _young_gen_sizer->min_desired_young_length();
+  }
  _young_gen_sizer->adjust_max_new_size(_g1h->max_regions());  // <------------- here!

Did not revert cleanly. Everything else is unchanged.

Testing: local compilation. tier1-tier3 running

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

Commit messages:
 - Revert "8249676: [REDO] G1 incorrectly limiting young gen size when using the reserve can result in repeated full gcs"

Changes: https://git.openjdk.java.net/jdk/pull/281/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=281&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8253411
  Stats: 412 lines in 3 files changed: 79 ins; 207 del; 126 mod
  Patch: https://git.openjdk.java.net/jdk/pull/281.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/281/head:pull/281

PR: https://git.openjdk.java.net/jdk/pull/281