Thanks Richard. It certainly does appear to be memory related (on a smaller data set of 250K subscribers, all accesses are < 1ms).
We're going to play with increasing RAM on the machine, and applying the optimisation levels on the page you recommended. (We're also running on a hardware RAID controlled SCSI set - mirrored disks so reading should be very fast). Cheers, Damien ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
