The problem seems to be memory. Running Debian latest with ispcfg3. tried optimizing apache, then placed nginx as a front-end proxy still the same problem. details about the server can be found here, its nice graphs and you will see the dire memory probs I am having: http://h1550830.stratoserver.net/munin/stratoserver.net/h1550830.stratoserver.net/index.html server details: model name : Dual-Core AMD Opteron(tm) Processor 1214 HE stepping : 3 cpu MHz : 2200.000 cache size : 1024 KB cat /proc/meminfo MemTotal: 4047116 kB MemFree: 944716 kB Buffers: 118796 kB Cached: 1522848 kB SwapCached: 407656 kB Active: 2422260 kB Inactive: 529960 kB SwapTotal: 2104496 kB SwapFree: 1046996 kB current situation: free total used free shared buffers cached Mem: 4047116 3219260 827856 0 118808 1555688 -/+ buffers/cache: 1544764 2502352 Swap: 2104496 1057392 1047104 running about 7-8 low traffic sites, mostly wordpress based. most of the sites didn't have more than 2GB of traffic the whole last year. only one of them had 30GB traffic over the last year. One of them sends out a daily newsletter at night to about 8000 recipients. current status looks like this: ls /etc/apache2/mods-enabled/ actions.conf alias.load authz_default.load authz_user.load cgi.load dir.conf fcgid.conf headers.load mime.load php5.conf rpaf.conf setenvif.conf ssl.load suexec.load actions.load auth_basic.load authz_groupfile.load autoindex.conf deflate.conf dir.load fcgid.load include.load negotiation.conf php5.load rpaf.load setenvif.load status.conf suphp.conf alias.conf authn_file.load authz_host.load autoindex.load deflate.load env.load headers.conf mime.conf negotiation.load rewrite.load ruby.load ssl.conf status.load suphp.load please also see screenshots. http://screencast.com/t/vg78MAuXi http://screencast.com/t/zxKoNAtohOP http://screencast.com/t/WbLjTqw7Q Please let me know if you need more info or if you have any suggestions.