Hi,
> > Since DSM is not available during postmaster, if we were to create a DSA > segment in place, similar to what's done in StatsShmemInit(), we would also > need to ensure that the initial shared memory is sized appropriately. This > is > because it would need to be large enough to accommodate all user-defined > tranches registered during postmaster, without having to rely on new > dsm segments. > From my experimentation, this sizing is not as straightforward as simply > calculating # of tranches * size of a tranche entry. > > I still think we should create the dsa during postmaster, as we do with > StatsShmemInit, but it would be better if postmaster keeps its hands off > this > dshash and only normal backends can use them. > > Thoughts? > > Since creating a DSA segment in place during Postmaster startup still requires calculating the size of the tranche names table including the user-defined tranches, why not use static shared memory to pre-allocate a fixed sized table and arrays of size NAMEDATALEN to store the names? If a dshash table is used to store tranche names and IDs, where would the tranche name for this table be registered? Thank you, Rahila Syed
