Can anyone help me improve poller performance

[cahonis]

Firstly, some cacti info:
cacti 0.8.7b
boost 2.5 (myisam)
PIA 2.1
mySQL 5.0
PHP 5.2.3

We have 140 hosts with around 3,900 data sources and poller times average about 195 seconds.

I have seen others on these forums with many thousands more data sources and similar or lower polling times. What can I do to improve my polling time?

MySQL my.ini settings:
max_connections=100
query_cache_size=100M
table_cache=256
tmp_table_size=52M
thread_cache_size=8
myisam_max_sort_file_size=100G
myisam_max_extra_sort_file_size=100G
myisam_sort_buffer_size=205M
key_buffer_size=349M
read_buffer_size=64K
read_rnd_buffer_size=256K
sort_buffer_size=256K

Thanks!

[BSOD2600]

1) cacti 0.8.7e + patches is now the current version.
2) if you're using cmd.php, increase the processes by a few.
3) if you're using spine, tweak the threads and oids per request.