From: Peter Ajamian (
Date: 02/22/00

Dave Ely wrote:
> I was reading through about the buffers and was wondering what a normal buffer switch
> was? Or if there is one?  The reason I ask, is that I looked at my stats and was kinda
> wondering why mine were so high lately.   Here is what I got:
I'm not positive about what I'm about to say but if I'm wrong I'm fairly
sure that someone will come along and correct me, so here goes...

This is nothing to worry about, see the comments interspersed...

> Current stats:
>       1 players in game      1 connected
>       9 registered
>    1407 mobiles            573 prototypes
>    1306 objects            683 prototypes
>    1966 rooms               36 zones
>       2 large bufs
      ^^^^^^^^^^^^^  Only 2 large buffers are being used, not bad,
CircleMUD will re-use a large buffer but will not destroy one, therefore
this number *should* also be the largest number of buffers in use at any
given time since the last reboot.  If this number starts growing then
you have something to worry about.

>     607 buf switches         0 overflows
      ^^^^^^^^^^^^^^  This is also nothing to worry about, all it is
saying is that the MUD switched from using a small buffer to a large
buffer a total of 607 times since the last reboot.  If you already have
large buffers allocated it will simply reuse them, it should not be
leaking memory for this.  If there are no existing large buffers
available then the MUD will simply create a new one and when it is no
longer needed it will be available for future use as well.
> and mind you, this was for 6 hours and with only 2 people playing at one time.
> Does this seem like an overly large amount of buf switches to you?

Well, that depends on the amount of activity, a lot of buffer switches
can occur if, for example, someone writes a really long board post, then
everyone reads it when they log in.  And yes, logging in can easily
cause a buffer switch, especially if you have a large MOTD, however, it
is nothing to worry about and should not cause any significant loss of
resources or performance.  Again, the number to watch is large bufs, if
that starts growing then you have something to worry about, buffer
switches is harmless.

> And if so, how would I go about finding why and fixing it?

Well, aside from rewriting the buffering system (which will probably be
done for 3.1 anyways), the only thing you can do to reduce this is to
limit things like MOTD, room descriptions, board posts, etc. to very
short ones, however, it is nothing to worry about, and I would not even
think of going to any trouble over it.

Regards, Peter

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