Hi, On 2021-12-13 00:00:23 +0100, Gunnar "Nick" Bluth wrote: > Regarding stats size; it adds one PgStat_BackendToastEntry > (PgStat_BackendAttrIdentifier + PgStat_ToastCounts, should be 56-64 bytes or > something in that ballpark) per TOASTable attribute, I can't see that make > any system break sweat ;-)
That's actually a lot. The problem is that all the stats data for a database is loaded into private memory for each connection to that database, and that the stats collector regularly writes out all the stats data for a database. > A quick run comparing 1.000.000 INSERTs (2 TOASTable columns each) with and > without "pgstat_track_toast" resulted in 12792.882 ms vs. 12810.557 ms. So > at least the call overhead seems to be neglectible. Yea, you'd probably need a few more tables and a few more connections for it to have a chance of mattering meaningfully. Greetings, Andres Freund