[Mailman-Users] want to slow down the post of server

hi,

i have a list about 36000 member in same domain.when i want to post an email and approve it there is not any problem in mailman server and gateways. but when it start to delivered to my sendmail server,my server load incresase so much and it stop to work properly. what can i do for this problem,i think about to slow down mailman's post, will it work?

Thanks,

Burcu İnci