Vacumm full done after each run.
pg_resetlog run between each server start

Scaling factor: 10
Initialization time: 
real    1m32.551s
user    0m1.710s
sys     0m0.130s

Kernel 2.4.20 
Effective cache size 38400 (300MB)
checkpoint segments=6

1)Shared buffers 1000

pgbench -c5 -t100 test1 
tps = 145.504917 (including connections establishing)
tps = 147.991299 (excluding connections establishing)

pgbench -c5 -t1000 test1
tps = 70.785341 (including connections establishing)
tps = 70.849065 (excluding connections establishing)

pgbench -c10 -t100 test1
tps = 147.605267 (including connections establishing)
tps = 149.944123 (excluding connections establishing)

pgbench -c10 -t1000 test1
tps = 55.646866 (including connections establishing)
tps = 55.678399 (excluding connections establishing)

2) Shared buffers 2000

pgbench -c5 -t100 test1
tps = 140.115444 (including connections establishing)
tps = 142.441377 (excluding connections establishing)

pgbench -c5 -t1000 test1
tps = 77.015876 (including connections establishing)
tps = 77.084474 (excluding connections establishing)

pgbench -c10 -t100 test1
tps = 128.512768 (including connections establishing)
tps = 130.314689 (excluding connections establishing)

pgbench -c10 -t1000 test1
tps = 55.003077 (including connections establishing)
tps = 55.035001 (excluding connections establishing)

3) Shared buffers 3000

pgbench -c5 -t100 test1
tps = 153.142499 (including connections establishing)
tps = 156.094637 (excluding connections establishing)

pgbench -c5 -t1000 test1
tps = 81.391878 (including connections establishing)
tps = 81.472845 (excluding connections establishing)

pgbench -c10 -t100 test1
tps = 120.420876 (including connections establishing)
tps = 122.066975 (excluding connections establishing)

pgbench -c10 -t1000 test1
tps = 56.766460 (including connections establishing)
tps = 56.801117 (excluding connections establishing)

4) Shared buffers 3000, noatime

pgbench -c5 -t100 test1
tps = 140.464589 (including connections establishing)
tps = 143.152323 (excluding connections establishing)

pgbench -c5 -t1000 test1
tps = 94.718161 (including connections establishing)
tps = 94.826618 (excluding connections establishing)

pgbench -c10 -t100 test1
tps = 131.925129 (including connections establishing)
tps = 133.826403 (excluding connections establishing)

pgbench -c10 -t1000 test1
tps = 65.374006 (including connections establishing)
tps = 65.458626 (excluding connections establishing)