On Sun, 28 Apr 2024 23:37:22 GMT, Vladimir Kozlov <k...@openjdk.org> wrote:

>> Move immutable nmethod's data from CodeCache to C heap. It includes 
>> `dependencies, nul_chk_table, handler_table, scopes_pcs, scopes_data, 
>> speculations`. 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. Call `vm_exit_out_of_memory()` 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.

Marked as reviewed by dlong (Reviewer).

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

PR Review: https://git.openjdk.org/jdk/pull/18984#pullrequestreview-2027786061

Reply via email to