• Edit /boot/loader.conf.local
• Change kern.ipc.nmbclusters=”0″ to kern.ipc.nmbclusters=”32768″
• Reboot the pfSense router

Some people have also seen a better performance by using the ufs cache filesystem setting. When using ufs filesystem you could possibly increase vfs.read_max=32 to vfs.read_max=128 in System -> Advanced -> Sytem Tunables.

refresh_pattern ([^.]+.|)(download|(windows|)update|).(microsoft.|)com/.*\.(cab|exe|msi|msp) 4320 100% 43200 reload-into-ims;
range_offset_limit -1;

refresh_pattern ([^.]+\.)?(download|(windows)?update)\.(microsoft\.)?com/.*\.(cab|exe|msi|msp|psf) 4320 100% 43200 reload-into-ims; range_offset_limit -1;

refresh_pattern ([^.]+.|)(download|adcdownload).(apple.|)com/.*\.(pkg|dmg) 4320 100% 43200 reload-into-ims;

refresh_pattern ([^.]+.|)avg.com/.*\.(bin) 4320 100% 43200 reload-into-ims;
refresh_pattern ([^.]+.|)spywareblaster.net/.*\.(dtb) 4320 100% 64800 reload-into-ims;
refresh_pattern ([^.]+.|)symantecliveupdate.com/.*\.(zip|exe) 43200 100% 43200 reload-into-ims
refresh_pattern ([^.]+.|)avast.com/.*\.(vpu|vpaa) 4320 100% 43200 reload-into-ims