Tailored Page Sizes

Main memory capacity continues to soar, resulting in TLB misses becoming an increasingly significant performance bottleneck. Current coarse grained page sizes, the solution from Intel, ARM, and others, have not helped enough. We propose Tailored Page Sizes (TPS), a mechanism that allows pages of size 2 ⁿ , for all n greater than a default minimum. For x86, the default minimum page size is 2 ¹² (4KB). TPS means one page table entry (PTE) for each large contiguous virtual memory space mapped to an equivalent-sized large contiguous physical frame. To make this work in a clean, seamless way, we suggest small changes to the ISA, the microarchitecture, and the O/S allocation operation. The result: TPS can eliminate approximately 98% of page walk memory accesses and 97% of all L1 TLB misses across a variety of SPEC17 and big data memory intensive benchmarks.