Tool for IO analysis?

Is there a tool for Win/Linux which shows me all file system hits on a webserver?

I once saw something like that for OS X with XCode. I want to improve the systems performance and I'm afraid I miss unnecessary "expensive" hits by Apache, MySQL o开发者_如何学编程r PHP.

Things I want to prevent:

• Apache scanning folders for .htaccess files
• PHP traversing for all include_path paths

There's strace. Start your apache with

$ strace -f -e open,access,stat -w apache2-io.log apache2

You can also attach with to a running process with the -p option. If you want to see the filesystem hits in real time, skip -w apache2-io.log.

Have a look at the manpage for more information.

On a Unix System you can use lsof (list open files), but beware, many files are open usually. You may want to filter the list somewhat, i.e. lsof | grep apache.