[Bug][performance] Performance degradation with -XX:+UseCompactObjectHeaders on streams about dragonwell11

[mmyxym]

Could you please provide completed test case?

Sorry, the import part is updated.

I have reproduced the issue and had the same result with lilliput-21u in lilliput project. The root cause is the heavy use of Klass* loading in test case. I would discuss with Lilliput project lead Roman on this issue. Thanks for the reporting!

[mmyxym]

Could you please provide completed test case?

Sorry, the import part is updated.

I have reproduced the issue and had the same result with lilliput-21u in lilliput project. The root cause is the heavy use of Klass* loading in test case. I would discuss with Lilliput project lead Roman on this issue. Thanks for the reporting!

dragonwell11/src/hotspot/cpu/x86/macroAssembler_x86.cpp

Line 5650 in 6c9ea3e

void MacroAssembler::load_nklass_compact(Register dst, Register src) {

Is this the "heavy use of Klass* loading" overhead you mentioned? I believe with lilliput several additional instructions will be generated for klass loading.

Yes, mainly from the monitor check:
testb(dst, markOopDesc::monitor_value);
jcc(Assembler::notZero, stub->entry());

[mmyxym]

AllMatcher.java:4: error: cannot find symbol
private LongPredicate op;
^
symbol: class LongPredicate
location: class AllMatcher
AllMatcher.java:7: error: cannot find symbol

Could you please provide completed test case?

[duanyangjing]

Could you please provide completed test case?

Sorry, the import part is updated.

[sendaoYan]

x64 ecs可以稳定复现：

yitian ecs可以稳定复现：

[mmyxym]

Beside the test case, do you see any significant slowdown on real workload or applications? We haven't seen noticeable performance regression on real workloads.

[duanyangjing]

Could you please provide completed test case?

Sorry, the import part is updated.

I have reproduced the issue and had the same result with lilliput-21u in lilliput project. The root cause is the heavy use of Klass* loading in test case. I would discuss with Lilliput project lead Roman on this issue. Thanks for the reporting!

dragonwell11/src/hotspot/cpu/x86/macroAssembler_x86.cpp

Line 5650 in 6c9ea3e

void MacroAssembler::load_nklass_compact(Register dst, Register src) {

Is this the "heavy use of Klass* loading" overhead you mentioned? I believe with lilliput several additional instructions will be generated for klass loading.

[duanyangjing]

Beside the test case, do you see any significant slowdown on real workload or applications? We haven't seen noticeable performance regression on real workloads.

Yes on some internal workload we have seen up to 10% degradation.

[mmyxym]

The issue is now on progress with the official Lilliput project. Close this issue.