Re: [PERFORM] The never ending quest for clarity on shared_buffers
Doug Y wrote: For idle persistent connections, do each of them allocate the memory specified by this setting (shared_buffers * 8k), or is it one pool used by all the connection (which seems the logical conclusion based on the name SHARED_buffers)? Personally I'm more inclined to think the latter choice, but I've seen references that alluded to both cases, but never a definitive answer. The shared_buffers are shared (go figure) :). It is all one pool shared by all connections. The sort_mem and vacuum_mem are *per*connection* however, so when allocating that size you have to take into account your expected number of concurrent connections. Paul ---(end of broadcast)--- TIP 6: Have you searched our list archives? http://archives.postgresql.org
Re: [PERFORM] The never ending quest for clarity on shared_buffers
On Thu, 2004-10-07 at 08:26, Paul Ramsey wrote: The shared_buffers are shared (go figure) :). It is all one pool shared by all connections. Yeah, I thought this was pretty clear. Doug, can you elaborate on where you saw the misleading docs? The sort_mem and vacuum_mem are *per*connection* however, so when allocating that size you have to take into account your expected number of concurrent connections. Allocations of size `sort_mem' can actually can actually happen several times within a *single* connection (if the query plan happens to involve a number of sort steps or hash tables) -- the limit is on the amount of memory that will be used for a single sort/hash table. So choosing the right figure is actually a little more complex than that. -Neil ---(end of broadcast)--- TIP 2: you can get off all lists at once with the unregister command (send unregister YourEmailAddressHere to [EMAIL PROTECTED])
