Any new ideas on JDK-8187338 (Per anonymous class class loader data is costly)?

[Andrew Dinn]

One small additional comment:

On 24/11/17 09:18, Andrew Dinn wrote:
> On 23/11/17 20:43, Thomas Stüfe wrote:
>> ...
>> Well, this sounds both simpler and more to the point than my proposal (2).
> 
> Not quite. We know that the "half-eaten-medium-chunk" problem is really
> a bad problem for anonymous class loaders and Zhengyu's patch improves
> that case. We don't know it is that is the only problem case. Other
> loaders may only load a small number of classes -- perhaps 1, maybe 2 --
> and also end up wasting a lot of space. If an app hits that case a lot
> then your proposal would allow the user to configure round it.
n.b. I'm not sure we need to worry much about any such apps as this
scenario is, arguably, very unlikely? I know, for example, that JBoss
Modules uses many classloaders but they rarely load just one or two
classes. Once you get to 3 or 4 classes I think the current behaviour
will be unlikely to increase waste because larger chunks means less
fragmentation. Are OSGi loaders likely to load just one or two classes
for a significant number of loaders?

regards,


Andrew Dinn
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