> > Only if you redefine the meaning of bgwriter_percent. At present it's > > defined by reference to the total number of dirty pages, and that can't > > be known without collecting them all. > > > > If it were, say, a percentage of the total length of the T1/T2 lists, > > then we'd have some chance of stopping the scan early.
> The other way around would make sense. In order to avoid writing the > busiest buffers at all (except for checkpoinging), the parameter should > mean "don't scan the last x% of the queue at all". Your meaning is 1 - above meaning (at least that is what Tom and I meant), but is probably easier to understand (== Informix LRU_MIN_DIRTY). > Still, we need to avoid scanning over all the clean blocks of a large > buffer pool, so there is need for a separate dirty-LRU. Maybe a "may be dirty" bitmap would be easier to do without beeing deadlock prone ? Andreas ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])