diff options
| -rw-r--r-- | storage/innobase/include/buf0buf.h | 16 | ||||
| -rw-r--r-- | storage/innobase/include/lock0lock.h | 13 |
2 files changed, 23 insertions, 6 deletions
diff --git a/storage/innobase/include/buf0buf.h b/storage/innobase/include/buf0buf.h index 2ad731e7b94..3f922708ef1 100644 --- a/storage/innobase/include/buf0buf.h +++ b/storage/innobase/include/buf0buf.h @@ -1726,10 +1726,15 @@ public: /** Hash table with singly-linked overflow lists. @see hash_table_t */ struct page_hash_table { + static_assert(CPU_LEVEL1_DCACHE_LINESIZE >= 64, "less than 64 bytes"); + static_assert(!(CPU_LEVEL1_DCACHE_LINESIZE & 63), + "not a multiple of 64 bytes"); + /** Number of array[] elements per page_hash_latch. Must be one less than a power of 2. */ - static constexpr size_t ELEMENTS_PER_LATCH= CPU_LEVEL1_DCACHE_LINESIZE / - sizeof(void*) - 1; + static constexpr size_t ELEMENTS_PER_LATCH= 64 / sizeof(void*) - 1; + static constexpr size_t EMPTY_SLOTS_PER_LATCH= + ((CPU_LEVEL1_DCACHE_LINESIZE / 64) - 1) * (64 / sizeof(void*)); /** number of payload elements in array[] */ Atomic_relaxed<ulint> n_cells; @@ -1746,7 +1751,12 @@ public: /** @return the index of an array element */ ulint calc_hash(ulint fold) const { return calc_hash(fold, n_cells); } /** @return raw array index converted to padded index */ - static ulint pad(ulint h) { return 1 + (h / ELEMENTS_PER_LATCH) + h; } + static ulint pad(ulint h) + { + ulint latches= h / ELEMENTS_PER_LATCH; + ulint empty_slots= latches * EMPTY_SLOTS_PER_LATCH; + return 1 + latches + empty_slots + h; + } private: /** @return the hash value before any ELEMENTS_PER_LATCH padding */ static ulint hash(ulint fold, ulint n) { return ut_hash_ulint(fold, n); } diff --git a/storage/innobase/include/lock0lock.h b/storage/innobase/include/lock0lock.h index 859441afcc0..c2fef3baaac 100644 --- a/storage/innobase/include/lock0lock.h +++ b/storage/innobase/include/lock0lock.h @@ -609,8 +609,9 @@ public: /** Number of array[] elements per hash_latch. Must be LATCH less than a power of 2. */ - static constexpr size_t ELEMENTS_PER_LATCH= CPU_LEVEL1_DCACHE_LINESIZE / - sizeof(void*) - LATCH; + static constexpr size_t ELEMENTS_PER_LATCH= (64 / sizeof(void*)) - LATCH; + static constexpr size_t EMPTY_SLOTS_PER_LATCH= + ((CPU_LEVEL1_DCACHE_LINESIZE / 64) - 1) * (64 / sizeof(void*)); /** number of payload elements in array[]. Protected by lock_sys.latch. */ ulint n_cells; @@ -632,9 +633,15 @@ public: /** @return the index of an array element */ inline ulint calc_hash(ulint fold) const; + /** @return raw array index converted to padded index */ static ulint pad(ulint h) - { return LATCH + LATCH * (h / ELEMENTS_PER_LATCH) + h; } + { + ulint latches= LATCH * (h / ELEMENTS_PER_LATCH); + ulint empty_slots= (h / ELEMENTS_PER_LATCH) * EMPTY_SLOTS_PER_LATCH; + return LATCH + latches + empty_slots + h; + } + /** Get a latch. */ static hash_latch *latch(hash_cell_t *cell) { |