Which operating system are you running on? The indexer can be CPU intensive, and can at times use all the CPU allocated to it. While crawling you can add page delays to slow it down.
If the high usage is during the walk phase you can add a small page delay such as .1 or .2 .
If during the creation of search indices there's probably not much you can do but nice the process. You can use "renice" to affect a running process or "nice" when starting a process.
Nice and renice are standard unix commands that you use from a shell prompt. See the unix man pages about them. To nice a walk/index process you'll need to launch it from the command line instead of from the web form. See the manual about running the walker by hand ( http://www.thunderstone.com/texis/site/ ... ing+dowalk ). Just put "nice" in front of the command.
nice texis profile=...
The last line of my previous response is an example of using nice. You need to complete it by reading the given url which has examples without the nice in front.
The page delays of .1 and .2 are values you might enter in the "Crawl Delay" of the Webinator walk settings admin page.