The problem is with the weird way of Intel testing and communication.
Every 3-6 month or so they will tell you the system is X% up or down on
arch Y (and they wont give you details because its somehow secret). And
then there are conflicting statements by the two or so performance test
departments. One of them repeatedly assured me that they do not see any
regressions.
Well the vmap fallback is generally useful AFAICT. Higher order
allocations are common on some of our platforms. Order 1 failures even
affect essential things like stacks that have nothing to do with SLUB and
the LBS patchset.
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