> i've been running tests with this patch for a few hours on my
> U5/270 without incident.  works for me!

Good.

I'm still trying to decide what the best compromise is in order to 
avoid excessive memory fragmentation (a danger with any pool based
allocation scheme) and still allow a fair degree of freedom for
configuring the buffer cache sizes. I'm thinking of using MAXBSIZE
pool page sizes for all buffer pools on machines with lots of
physical memory, while being more economical on low memory machines.


Anyway, here are a few statistics i've collected in the past days..


A `systat buf' sample on a 32MB sparcstation with default parameters
after 5 days of casual use.

                    /0   /1   /2   /3   /4   /5   /6   /7   /8   /9   /10
     Load Average   ||

There are 1871 metadata buffers using            9724 kBytes of memory.
There are 1672 pages for cached file data using  6688 kBytes of memory.
There are  561 pages for executables using       2244 kBytes of memory.

File System          Bufs used   %   kB in use   %  Bufsize kB   %  Util %
/usr                       804  42        2269  23        2285  23      99
/usr/src                   492  26        3936  40        3936  40     100
/                          150   8         523   5         524   5     100
[all NFS filesystems from here]]
/home                        9   0          58   1          58   1     100
/usr/pkg                     7   0          56   1          56   1     100
/altroot                     7   0          14   0          14   0     100
/altroot/usr                 2   0           9   0           9   0     100
/usr/local/share             1   0           8   0           8   0     100
/usr/pkgsrc                  1   0           8   0           8   0     100
/usr/xsrc                    1   0           8   0           8   0     100

Total:                    1474  78        6889  71        6906  71     100


Here's a `systat buf' sample on a 650MB machine (i386, PII) with bufcache
turned up to 80%, and after running `find / -name xxxx':

                    /0   /1   /2   /3   /4   /5   /6   /7   /8   /9   /10
     Load Average   |||          

There are  89497 metadata buffers using           331531 kBytes of memory.
There are     84 pages for cached file data using    336 kBytes of memory.
There are    727 pages for executables using        2908 kBytes of memory.

File System          Bufs used   %   kB in use   %  Bufsize kB   %  Util %
/mnt/lfs                 29464  32       34767  10       34927  11     100
/mnt/nfs                 11522  12       92176  28       92176  28     100
/mnt/ufsv2                4300   4       46542  14       46542  14     100
/                         1571   1        2597   1        2631   1      99

Total:                   46857  52      176082  53      176276  53     100



This is my local NFS server (running a 3-week old kernel btw, w/ previously
posted patches):

                    /0   /1   /2   /3   /4   /5   /6   /7   /8   /9   /10
     Load Average   |

There are 13304 metadata buffers using            47881 kBytes of memory.
There are   249 pages for cached file data using    996 kBytes of memory.
There are  1135 pages for executables using        4540 kBytes of memory.

File System          Bufs used   %   kB in use   %  Bufsize kB   %  Util %
/z                       13119  98       47000  98       47000  98     100
/                          129   0         576   1         576   1     100
/usr                        56   0         305   1         305   1     100

Total:                   13304 100       47881 100       47881 100     100