> ### Summary > `os::committed_in_range` is used by NMT to account for thread stacks. The > name is misleading, it actually is meant to find **live** pages not just > **committed** pages. On POSIX (except AIX) this works correctly using > `mincore`. On Windows this worked incorrectly using `VirtualQuery` (only > finds committed, not live regions). This means that the values reported on > Windows were inaccurate. > > This PR fixes the Windows implementation by using `QueryWorkingSetEx` instead > of `VirtualQuery`. This properly identifies pages that are truly live in the > working set, not just committed. I also renamed `committed_in_range` to > `resident_in_range` so that the intention is clearer. I have tried to > structure the Windows implementation as similarly to Posix as possible to > help with maintainability. > > ### Testing > - Tested on windows and linux and64 > - `make test TEST=gtest:NMTCommittedVirtualMemory` (this tests > `live_in_range` directly) > - `make test > TEST=test/hotspot/jtreg/runtime/Thread/TestAlwaysPreTouchStacks.java` (this > tests `resident_in_range` indirectly through NMT thread stack accounting) > - `make test TEST=gtest:os` > - `make test TEST=hotspot_nmt` > - tier 1 > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai).
Robert Toyonaga has updated the pull request incrementally with one additional commit since the last revision: do suggested renaming to first_resident_in_range ------------- Changes: - all: https://git.openjdk.org/jdk/pull/31124/files - new: https://git.openjdk.org/jdk/pull/31124/files/80c86886..e6ef89f0 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=31124&range=04 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=31124&range=03-04 Stats: 16 lines in 5 files changed: 0 ins; 0 del; 16 mod Patch: https://git.openjdk.org/jdk/pull/31124.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/31124/head:pull/31124 PR: https://git.openjdk.org/jdk/pull/31124
