Hi, On 2025-07-14 03:28:16 +0900, Masahiko Sawada wrote: > I've reviewed the 0001 and 0002 patches. The API implemented in the > 0002 patch looks good to me, but I'm concerned about the capsulation > of copy state data. With the v42 patches, we pass the whole > CopyToStateData to the extension codes, but most of the fields in > CopyToStateData are internal working state data that shouldn't be > exposed to extensions. I think we need to sort out which fields are > exposed or not. That way, it would be safer and we would be able to > avoid exposing copyto_internal.h and extensions would not need to > include copyfrom_internal.h. > > I've implemented a draft patch for that idea. In the 0001 patch, I > moved fields that are related to internal working state from > CopyToStateData to CopyToExectuionData. COPY routine APIs pass a > pointer of CopyToStateData but extensions can access only fields > except for CopyToExectuionData. In the 0002 patch, I've implemented > the registration API and some related APIs based on your v42 patch. > I've made similar changes to COPY FROM codes too.
I've not followed the development of this patch - but I continue to be concerned about the performance impact it has as-is and the amount of COPY performance improvements it forecloses. This seems to add yet another layer of indirection to a lot of hot functions like CopyGetData() etc. Greetings, Andres Freund
