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Date: 	Mon, 26 Jun 1995 10:32:28 -0700 (PDT)
From: Tom Samplonius <tom@uniserve.com>
To: "=?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?= aka Andrey A. Chernov, Black Mage" <ache@astral.msk.su>
cc: John Capo <jc@irbs.com>,
        freebsd-current <freebsd-current@freefall.cdrom.com>
Subject: Re: mb_map full with GATEWAY and maxusers 64!
In-Reply-To: <pSIbkxlaU5@astral.msk.su>
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On Mon, 26 Jun 1995, =?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?= aka Andrey A. Chernov, Black Mage wrote:

> >I have seen it with maxusers at 48 and 96 on a lightly loaded system.
> >I switched to NMBCLUSTERS=2048 and have not seen it since.
> 
> Maybe we need simple increase NMBCLUSTERS calculation as default to
> something like:
> 
> #ifdef GATEWAY
> #define NMBCLUSTERS (2048 + maxusers * 16)
> #else
> #define NMBCLUSTERS (1024 + maxusers * 16)
> #endif
> 
> Any opinions?

  I think that is too high.  Most (all?) users that reported this problem 
found that 2048 buffers cured it.  Yet your calculcation would give these 
users even more buffers that would likely be unneeded.

  As an alternative:

  - document NMBCLUSTERS in LINT (as of 2.0.5R, this still wasn't mentioned)
  - include a explicit "options NMBCLUSTERS" line in the GENERIC kernel, 
with then note that "mb_map" full indicates that you've run out these buffers

  I would just prefer that this just be documented rather than to bury the 
calculation somewhere.

Tom