Chrome runs each tab as a separate process running them in complete isolation. This means it can be extremely quick however it does mean that more memory is being used. Even tabs running the background are kept running to allow pages to refresh and be ready if you refer back to them. Other web browsers are also adopting this method of separate processes however we’ve seen a number of instances where Chrome is eating a huge amount of memory. As an example, below is a screenshot of all the Chrome processes and their memory use from a machine which had just 4 tabs open at the time.
There are a number of 3rd party add-ons which can reduce the amount of memory that Chrome uses. However by far the simplest way of controlling it is not to have lots of tabs open at once as well as changing settings such as not reloading all previous running tabs when you start it.