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diff --git a/storage/rocksdb/rocksdb/third-party/folly/folly/lang/Align.h b/storage/rocksdb/rocksdb/third-party/folly/folly/lang/Align.h
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+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#pragma once
+
+#include <cstdint>
+
+namespace folly {
+
+//  Memory locations within the same cache line are subject to destructive
+//  interference, also known as false sharing, which is when concurrent
+//  accesses to these different memory locations from different cores, where at
+//  least one of the concurrent accesses is or involves a store operation,
+//  induce contention and harm performance.
+//
+//  Microbenchmarks indicate that pairs of cache lines also see destructive
+//  interference under heavy use of atomic operations, as observed for atomic
+//  increment on Sandy Bridge.
+//
+//  We assume a cache line size of 64, so we use a cache line pair size of 128
+//  to avoid destructive interference.
+//
+//  mimic: std::hardware_destructive_interference_size, C++17
+constexpr std::size_t hardware_destructive_interference_size = 128;
+
+//  Memory locations within the same cache line are subject to constructive
+//  interference, also known as true sharing, which is when accesses to some
+//  memory locations induce all memory locations within the same cache line to
+//  be cached, benefiting subsequent accesses to different memory locations
+//  within the same cache line and heping performance.
+//
+//  mimic: std::hardware_constructive_interference_size, C++17
+constexpr std::size_t hardware_constructive_interference_size = 64;
+
+} // namespace folly
+