statistics buffer is full

What does the message 'statistics buffer is full' mean?  And if I saw lots of
these in my logs what sort of bad things would happen?  Presumably this is
related to the planner statistics?  Would I expect to have bad plans if this
happens and how would I resolve it?  This is what I found in the source, but
I'm not really sure what's going on here:

Part of:

pgstat_recvbuffer(void)
<snip>
                 /*
                  * As long as we have buffer space we add the socket to the read
                  * descriptor set.
                  */
                 if (msg_have <= (int) (PGSTAT_RECVBUFFERSZ - sizeof(PgStat_Msg))
)
                 {
                         FD_SET(pgStatSock, &rfds);
                         maxfd = pgStatSock;
                         overflow = false;
                 }
                 else
                 {
                         if (!overflow)
                         {
                                 ereport(LOG,
                                                 (errmsg("statistics buffer is full")));
                                 overflow = true;
                         }
                 }


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Jeff Frost, Owner     <jeff@frostconsultingllc.com>
Frost Consulting, LLC     http://www.frostconsultingllc.com/
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