RFR: 8354452: Shenandoah: Enforce range checks on parameters controlling heuristic sleep times

[Y. Srinivas Ramakrishna]

On Fri, 11 Apr 2025 20:41:00 GMT, William Kemper <wkemper at openjdk.org> wrote:

> Without enforcing limits on `ShenandoahControlIntervalMin` and `ShenandoahControlIntervalMax`, the user may supply values that cause assertions to fail.
> 
> This assertion failure has been observed in Genshen's regulator thread:
> 
> #0 0x000028e8062d021a in ShenandoahRegulatorThread::regulator_sleep (this=0x4ef9701893b0) at src/hotspot/share/gc/shenandoah/shenandoahRegulatorThread.cpp:125
> #1 0x000028e8062d0027 in ShenandoahRegulatorThread::regulate_young_and_old_cycles (this=0x4ef9701893b0) at src/hotspot/share/gc/shenandoah/shenandoahRegulatorThread.cpp:95
> #2 0x000028e8062cfd06 in ShenandoahRegulatorThread::run_service (this=0x4ef9701893b0) at src/hotspot/share/gc/shenandoah/shenandoahRegulatorThread.cpp:51
> 
> But it could just as easily happen in other modes to the `ShenandoahControlThread` instance.

Left a comment for consideration but changes look fine if this changes doesn't interfere with potential tuning space etc.

src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp line 1:

> 1: /*

Change looks fine, but I wonder about using a `naked_sleep()` and allowing longer durations without triggering asserts in those cases? Not sure where this could be used and whether 1-second is the maximum we might like for these numbers regardless.

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Marked as reviewed by ysr (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24602#pullrequestreview-2761556102
PR Review Comment: https://git.openjdk.org/jdk/pull/24602#discussion_r2040287010