Greetings, On Tue, May 25, 2021 at 15:09 Robert Haas <robertmh...@gmail.com> wrote:
> On Tue, May 25, 2021 at 2:45 PM Bruce Momjian <br...@momjian.us> wrote: > > Well, if we create a separate nonce counter, we still need to make sure > > it doesn't go backwards during a crash, so we have to WAL log it > > I think we don't really need a global counter, do we? We could simply > increment the nonce every time we write the page. If we want to avoid > using the same IV for different pages, then 8 bytes of the nonce could > store a value that's different for every page, and the other 8 bytes > could store a counter. Presumably we won't manage to write the same > page more than 2^64 times, since LSNs are limited to be <2^64, and > those are consumed more than 1 byte at a time for every change to any > page anywhere. The nonce does need to be absolutely unique for a given encryption key and therefore needs to be global in some form. Thanks! Stephen
