review(XS): 7145345: Code cache sweeper must cooperate with safepoints

[Tom Rodriguez]

On Feb 14, 2012, at 1:08 PM, Igor Veresov wrote:

> I tried that. It made no measurable difference. I figured it's better to start running a compile while we're doing GC, which is what will happen after the bailout.

So it's not about yielding to a safepoint?  It's about starting the compile sooner?  Then I think you should gate the amount of work the sweeper does instead.  That would actually tend to distribute the sweeper work between different compiler threads better.  Right now a single compile can be delayed a long time because it's trying to process a quarter of the cache.

tom

> 
> igor
> 
> On Tuesday, February 14, 2012 at 1:04 PM, Tom Rodriguez wrote:
> 
>> 
>> On Feb 14, 2012, at 12:36 PM, Igor Veresov wrote:
>> 
>>> Code cache sweeper must yield to safepoint. With high numbers of methods sweeping can block the safepoint from happening.
>> 
>> Why don't you just safepoint instead of aborting the current sweep?
>> 
>> We may also want to increase the sweep fraction for tiered.
>> 
>> tom
>> 
>>> 
>>> Webrev: http://cr.openjdk.java.net/~iveresov/7145345/webrev.00/
>>> 
>>> 
>>> igor
>