Hi All, I understand the storage layer in databases goes to great lengths to ensure: - a row does not cross a block boundary - read/writes/allocation happen in units of blocks etc. The motivation is that at the OS level, it reads and writes pages (blocks), not individual bytes. I am only concerned about SSDs but I think the principle applies to HDD as well.
but how can we do all this when we are not even guaranteed that the beginning of a file will be aligned with a block boundary? refer this <https://stackoverflow.com/questions/8018449/is-it-guaranteed-that-the-beginning-of-a-file-is-aligned-with-pagesize-of-file-s> . Further, I don't see any APIs exposing I/O operations in terms of blocks. All File I/O APIs I see expose a file as a randomly accessible contiguous byte buffer. Would it not have been easier if there were APIs that exposed I/O operations in terms of blocks? can someone explain this to me? Sid
