Need some advice from a Server/VPS pro to optimize my VPS

Hi,
I have been having the same problems as well on my VPS. What they told me is that there is to many instances and the the parent server was shutting down my apache and sql.

I started investigating as i have a number of wordpress site. First do site:sitename.com to how your site is indexed. Goto say 15 - 20 page in and you will (or might) find a lot of crap pages indexed.

One of my site that had 55000 pages indexed on google got removed because of this. (these bad pages - the 55000 pages was legit articles)

Also check your awstats for strange page being visit.

Goto the wp-content upload directory and you will find a
htaccess file and a php file in a number form e.g. 284727.php
The numbers is different. You can have these on every months directory
if you have many. Get rid of those as they are the culprits. Also you make sure you use ftp or ssh as these files are hidden in cpanel

I have found one site that was so bad and caused the load to spike and that is when sql and apache fails.

I am also monitoring http with hyperspin now that if my data center can't pick it up quickly i can act fast to restart apache.

I have just under 200 sites on my vps and have inspected +- 60 so far and +- 30 of the wordpress installation had these files on them. I am busy upgrading all to latest wordpress and it seems to help.

I am not 100% sure how to rectify the problem as i am think of installing a plugin that protect those directories.

Not sure if your problem is the same but check it out as i tried everything and we optimized the VPS a few times but that didn't solve the problem

Without discussing wordpress related issues (a whole kettle of fish on its own and the poster above me offered some solid starting points)

Here's 2 really simple solutions to saving a lot of ram, I use on my own and all my clients VPSes

1 - Replace apache with Lighttpd. Dont be scared, it does all the same things you can do in apache except it doesnt use htaccess. It is however very easy to get the same functions as htaccess would provide (pretty urls, wildcard subdomains etc etc)

2 - Replace BIND9 with tinyDNS (if you're running a nameserver)

Neither of these will pose any problems or security flaws and will save easy up to 200mb of ram or more on an idle system, so imagine the benefit on a trafficked VPS.

there is obviously more you can do, but not knowing exactly how you have tweaked your mysql or what exactly else you have on your server I wouldnt really feel comfortable elaborating anymore.

Check that the mysql query cache is enabled. If it's not, turn it on. In /etc/my.cnf, look for query_cache_size.

[mysqld]
...
query_cache_size=20M

If it's not there, or set to 0, set it to something (8M, 16M, something).

Also, double check your code to see if pconnect() is being used in any of your PHP code.