RFR 8012371: Adjust Tiered compile threshold according to available space in codecache

[Albert Noll]

Hi,

Thanks again for looking at the code. I made the proposed changes.

http://cr.openjdk.java.net/~anoll/8012371/webrev.02/


I also thought about adding:

if (CodeCache::needs_flushing()) {
   return Double.MAX_VALUE;
}

Before:

// Increase C1 compile threshold when the code cache is filled more
// than specified by IncreaseFirstTierCompileThresholdAt percentage.
// The main intention is to keep enough free space for C2 compiled code
// to achieve peak performance if the code cache is under stress.
if ((TieredStopAtLevel == CompLevel_full_optimization) && (level != CompLevel_full_optimization))  {
   double current_reverse_free_ratio = CodeCache::reverse_free_ratio();
   if (current_reverse_free_ratio > _increase_threshold_at_ratio) {
     k *= exp(current_reverse_free_ratio - _increase_threshold_at_ratio);
   }
}


What do you think?

Thanks for looking again :-)

Albert

On 16.05.2013 04:44, Igor Veresov wrote:
> Sure :)
>
> igor
>
> On May 15, 2013, at 2:34 PM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
>
>> On 5/15/13 1:32 PM, Igor Veresov wrote:
>>> Well, there is a Tier23InlineeNotifyFreqLog option there already.. :)
>> I did not know about that flag but I still would like to use FirstTier.
>>
>> Thanks,
>> Vladimir
>>
>>> But I'm not insisting. Hopefully not too many people will have to tweak any of that.
>>>
>>> igor
>>>
>>> On May 15, 2013, at 11:02 AM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
>>>
>>>> Tier23 could be confusing - we don't have 23 levels of tier :)
>>>> That is why I thought FirstTier is more general name for Tier1, Tier2, Tier3.
>>>>
>>>> Vladimir
>>>>
>>>> On 5/15/13 9:53 AM, Igor Veresov wrote:
>>>>> May I also comment about that option name?
>>>>> Most tier-specific options in are in the form of TierXFooBar, where X is a compilation level(s). So, may be IncreaseTier23CompileThresholdAt?
>>>>>
>>>>> igor
>>>>>
>>>>> On May 15, 2013, at 9:04 AM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
>>>>>
>>>>>> IncreaseFirstTierCompileThresholdAt