RFR: 8331185: Enable compiler memory limits in debug builds [v5]
Thomas Stuefe
stuefe at openjdk.org
Mon Apr 29 18:48:16 UTC 2024
> See [1] for previous discussions.
>
> We'd like to introduce a default memory limit for compilations in debug builds. That way, we can catch pathological compiler errors that have an unreasonably high per-compilation memory footprint early during testing.
>
> The default limit affects all compilations, unless the method is subject to a memory limit set from command line. Meaning, `-XX:CompileCommand=MemLimit,...` overrules the default.
>
> Examples:
>
> This lowers the memlimit for j.l.String methods - all methods will have the default 1GB limit in a debug JVM. Only j.l.String will run with a 100M limit: `-XX:CompileCommand=MemLimit,java.lang.String::*,100m`
>
> This disables the default memlimit globally: `-XX:CompileCommand=MemLimit,*.*,0`
>
>
> ---
>
> The patch:
>
> 1) adds a debug-only default memory limit of **1GB** (as proposed by @vnkozlov). The limit action is "crash", meaning we will assert.
> 2) To test the mechanics, we now print out the memory limit for each compilation in the compilation cost record.
> 3) Adapted and extended tests
>
> I also fixed up some copyrights that I overlooked last year when adding the compiler memory statistics this patch builds atop of.
>
>
> Tested:
>
> - manually on Mac m1 (debug and release)
> - GHAs are running
> - but Oracle will do more testing before this goes in
>
> [1] https://mail.openjdk.org/pipermail/hotspot-compiler-dev/2024-April/074787.html
Thomas Stuefe has updated the pull request incrementally with two additional commits since the last revision:
- another fix
- fix accidental slip in of another test name
-------------
Changes:
- all: https://git.openjdk.org/jdk/pull/18969/files
- new: https://git.openjdk.org/jdk/pull/18969/files/42f36401..d06406ec
Webrevs:
- full: https://webrevs.openjdk.org/?repo=jdk&pr=18969&range=04
- incr: https://webrevs.openjdk.org/?repo=jdk&pr=18969&range=03-04
Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
Patch: https://git.openjdk.org/jdk/pull/18969.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/18969/head:pull/18969
PR: https://git.openjdk.org/jdk/pull/18969
More information about the hotspot-compiler-dev
mailing list