[aarch64-port-dev ] Support large codecache for JDK8

[Andrew Dinn]

On 10/03/15 10:53, Andrew Haley wrote:
> On 03/10/2015 10:28 AM, Andrew Dinn wrote:
>> Ok to push?
> 
> It looks reasonable.  Does the large code cache kick in with the default
> configuration?  Do we want it to?

This is essentially the same patch as was applied to 9. So, the code
cache size is driven by the value of ReservedCodeCache size.

That variable defaults to 48*M but with tiered it gets multiplied up to
5 times that i.e. 240*M and then rounded back down to 128*M by this code:

  // Increase the code cache size - tiered compiles a lot more.
  if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
    FLAG_SET_ERGO(uintx, ReservedCodeCacheSize,
                  MIN2(CODE_CACHE_DEFAULT_LIMIT, ReservedCodeCacheSize *
5));
  }

... and, of course, 128*M is the threshold value above which far
branches become necessary.

In other words the answer to your first question is no.

I don't know the answer to the second question. Anyone who wants a
larger cache can select it by setting ReservedCodeCache. Is this in some
way inadequate?

regards,


Andrew Dinn
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