On Fri, Jul 15, 2022 at 8:33 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > Zhihong Yu <z...@yugabyte.com> writes: > > I was looking at the code in use_physical_tlist(). > > In the code block checking CP_LABEL_TLIST, I noticed that > > the Bitmapset sortgroupatts is not freed before returning from the > method. > > Looking at create_foreignscan_plan() (in the same file): > > bms_free(attrs_used); > > It seems the intermediate Bitmapset is freed before returning. > > TBH, I'd say that it's probably the former code not the latter > that is good practice. Retail pfree's in code that's not in a > loop very possibly expend more cycles than they are worth, because > the space will get cleaned up anyway when the active memory > context is reset, and pfree is not as cheap as one might wish. > It might be possible to make a case for one method over the other > with some study of the particular situation, but you can't say > a priori which way is better. > > On the whole, I would not bother changing either of these bits > of code without some clear evidence that it matters. It likely > doesn't. It's even more likely that it doesn't matter enough > to be worth investigating. > > regards, tom lane > Hi, Tom: Thanks for responding over the weekend.
I will try to remember what you said. Cheers
