> Move immutable nmethod's data from CodeCache to C heap. It includes > `dependencies, nul_chk_table, handler_table, scopes_pcs, scopes_data, > speculations, jvmci_data`. It amounts for about 30% (optimized VM) of space > in CodeCache. > > Use HotSpot's `os::malloc()` to allocate memory in C heap for immutable > nmethod's data. Bail out compilation if allocation failed. > > Shuffle fields order and change some fields size from 4 to 2 bytes to avoid > nmethod's header size increase. > > Tested tier1-5, stress,xcomp > > Our performance testing does not show difference. > > Example of updated `-XX:+PrintNMethodStatistics` output is in JBS comment.
Vladimir Kozlov has updated the pull request incrementally with one additional commit since the last revision: Address comments. Moved jvmci_data back to mutable data section. ------------- Changes: - all: https://git.openjdk.org/jdk/pull/18984/files - new: https://git.openjdk.org/jdk/pull/18984/files/6b1f69d9..1824f46c Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=18984&range=01 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18984&range=00-01 Stats: 98 lines in 5 files changed: 39 ins; 36 del; 23 mod Patch: https://git.openjdk.org/jdk/pull/18984.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/18984/head:pull/18984 PR: https://git.openjdk.org/jdk/pull/18984
