MongoDB 3.2.8 ignores ulimit in systemd distributions

Hello, I just update some mongod servers to 3.2.8 and I noticed that max open files setting is not respected. db.serverStatus().connections returns a maximum of 819 connections while the ulimit -n is correctly set at 65536

My servers runs under Debian Jessie and before upgrading package I changed the source from wheezy to jessie repository

This affects only the jessie version.

I also tested this on a fresh new server to check if this was coming from my previous configuration and the result is the same, still capped at 819 connections.

As I can't download pre 3.2.8 version with the Jessie source I wasn't able to see if this was affecting previous versions.

Is the max open files limitation handled differently on Jessie ?

Thanks