Hi, I've recently seen a benchmark in which pg_mbcliplen() showed up prominently. Which it will basically in any benchmark with longer query strings, but fast queries. That's not that uncommon.
I wonder if we could avoid the cost of pg_mbcliplen() from within pgstat_report_activity(), by moving some of the cost to the read side. pgstat values are obviously read far less frequently in nearly all cases that are performance relevant. Therefore I wonder if we couldn't just store a querystring that's essentially just a memcpy()ed prefix, and do a pg_mbcliplen() on the read side. I think that should work because all *server side* encodings store character lengths in the *first* byte of a multibyte character (at least one clientside encoding, gb18030, doesn't behave that way). That'd necessitate an added memory copy in pg_stat_get_activity(), but that seems fairly harmless. Faults in my thinking? Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers