cache manager process exited with fatal code 2 and cannot be respawned

[Isaac Hailperin]

Hi,

after restarting nginx I find

2012/11/07 10:24:02 [alert] 23635#0: 512 worker_connections are not enough
2012/11/07 10:24:02 [alert] 23636#0: 512 worker_connections are not enough
2012/11/07 10:24:04 [alert] 23618#0: cache manager process 23635 exited 
with fatal code 2 and cannot be respawned

in my logs. It seems like this error came up after adding more then 2500 
virtual hosts, each consisting of two server blocks, one for http, and 
one for https.

Now I don't quite understand these messages. In my nginx.conf I have
user www-data;
worker_processes 16;
pid /var/run/nginx.pid;
worker_rlimit_nofile 65000;

events {
         worker_connections 2000;
         use epoll;
         # multi_accept on;
}

so that should be enough worker_connections. Why am I still getting this 
message?

For the other message regarding the cache manger, I found this
http://www.ruby-forum.com/topic/519162
thread, where Maxim Dounin suggests that it results from the kernel not 
supporting eventfd(). But as far as I understand this is only an issue 
with kernels bevore 2.6.18. I use 2.6.32 and my kernel config clearly 
states
CONFIG_EVENTFD=y

Here is the nginx version and configure options:
root at debian:~# nginx -V
nginx version: nginx/1.2.4
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx/ --sbin-path=/usr/sbin/nginx 
--conf-path=/etc/nginx/nginx.conf 
--error-log-path=/var/log/nginx/error.log 
--http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid 
--lock-path=/var/run/nginx.lock 
--http-client-body-temp-path=/var/cache/nginx/client_temp 
--http-proxy-temp-path=/var/cache/nginx/proxy_temp 
--http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp 
--http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp 
--http-scgi-temp-path=/var/cache/nginx/scgi_temp --user=nginx 
--group=nginx --with-http_ssl_module --with-http_realip_module 
--with-http_addition_module --with-http_sub_module 
--with-http_dav_module --with-http_flv_module --with-http_mp4_module 
--with-http_gzip_static_module --with-http_random_index_module 
--with-http_secure_link_module --with-http_stub_status_module 
--with-mail --with-mail_ssl_module --with-file-aio --with-ipv6

Any ideas?

Isaac