Complex sentence: Sequential I/O is not cached, in order to avoid rapid SSD cache invalidation on such operations that are already suitable enough for HDDs; going around the cache for big sequential writes is known as the write-around policy.
Split into simpler sentences: Sequential I/O is not cached, in order to avoid rapid SSD cache invalidation on such already suitable enough operations for HDDs. Going around the cache for big sequential writes is known as the write-around policy.