Hi, On 2024-10-26 16:14:25 +0200, Alvaro Herrera wrote: > > A fixed-size shared memory block, currently accommodating 30 records, > > is used to store the statistics. > > Hmm, would it make sene to use dynamic shared memory for this?
+1 > The publishing backend could dsm_create one DSM chunk of the exact size that > it needs, pass the dsm_handle to the consumer, and then have it be destroy > once it's been read. I'd probably just make it a dshash table or such, keyed by the pid, pointing to a dsa allocation with the stats. > That way you don't have to define an arbitrary limit > of any size. (Maybe you could keep a limit to how much is published in > shared memory and spill the rest to disk, but I think such a limit should be > very high[1], so that it's unlikely to take effect in normal cases.) > > [1] This is very arbitrary of course, but 1 MB gives enough room for > some 7000 contexts, which should cover normal cases. Agreed. I can see a point in a limit for extreme cases, but spilling to disk doesn't seem particularly useful. Greetings, Andres Freund
