I don't think you'll see any difference between 57 and 64.

It looks like LG_VADDR is used to decide which bits in an internal pointer can be reused. On arm64 if the value is at most 56 then RTREE_LEAF_COMPACT is defined so parts of the pointer are reused, if it's 57 then it's not and struct rtree_leaf_elm_s pulls the index and slab bit out.

On arm64 the value could be 52 for when FEAT_LPA2 is implemented.

Do you see any performance or memory usage change with this?

In D46686#1064294, @andrew wrote:

I don't think you'll see any difference between 57 and 64.

It looks like LG_VADDR is used to decide which bits in an internal pointer can be reused. On arm64 if the value is at most 56 then RTREE_LEAF_COMPACT is defined so parts of the pointer are reused, if it's 57 then it's not and struct rtree_leaf_elm_s pulls the index and slab bit out.

On arm64 the value could be 52 for when FEAT_LPA2 is implemented.

Do you see any performance or memory usage change with this?

Machine which I have is unusable for any perf work (BIOS is too broken). Perhaps I should add an option for small/large jemalloc VADDR. default to large?

Ping? This is the last bit to restore LA57.

If JEMALLOC_LG_VADDR_WIDE is default YES we need a WITHOUT_JEMALLOC_LG_VADDR_WIDE description - src.conf documents the non-default setting. Otherwise LGTM.