RFR: 8344882: (bf) Temporary direct buffers should not count against the upper limit on direct buffer memory [v2]

[Alan Bateman]

On Mon, 25 Nov 2024 18:51:48 GMT, Brian Burkhalter <bpb at openjdk.org> wrote:

>> Make the memory used by internal temporary direct buffers not count towards the upper limit on direct buffer memory.
>
> Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8344882: Do not create Cleaner for temporary buffers

src/java.base/share/classes/java/nio/Direct-X-Buffer.java.template line 77:

> 75:     static final boolean UNALIGNED = Bits.unaligned();
> 76: 
> 77:     private @Stable boolean temporary; // defaults to false

Is this used now?

src/java.base/share/classes/jdk/internal/access/JavaNioAccess.java line 73:

> 71:      * Used by {@code sun.nio.ch.Util}.
> 72:      */
> 73:     ByteBuffer allocateDirectTemporary(int cap);

In Util, the phrase used is "temporary buffer and the methods are named like getTemporaryDirectBuffer. The SharedSecrets transposes the words, don't know if that was intended or not.

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PR Review Comment: https://git.openjdk.org/jdk/pull/22339#discussion_r1857208729
PR Review Comment: https://git.openjdk.org/jdk/pull/22339#discussion_r1857210986