Segmentation fault with NUMA aware ParallelScavange GC

[Lokesh Gidra]

>
>The only thing I can think of is that we started using 
>madvise(MADV_FREE) to uncommit pages in lgrp chunks instead of doing 
>mmap over mmap. I've tested it with earlier kernels and it works fine. 
>It could be the semantics of MADV_FREE somehow changed. jdk6u25 has 
>still the hotspot that would do mmap. So running it would confirm the 
>theory.
>
But isn't madvise(MADV_FREE) just frees the pages rather than removing the vma region all together? 


Can you please tell me which kernel version did it work fine with? I tried with 6b20 and its still the same. I will try with jdk6u25 as well and let you know.


>Alternatively, if you're open to building hotspot, I can send you a 
>patch to try.

Yes, I am. Please send me the patch.

>
>igor
>
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