V8 powers Google's Chrome

The Google Chrome browser is based on a new Javascript virtual machine called V8 developed by Google engineers in Denmark. V8 interprets Java code and compiles it directly to the machine language of the CPU, presumably an x86 processor.

V8 supports "hidden class transactions" to better group and manage objects. It has improved garbage collection that can make a round trip of memory in "a few milliseconds."

Google claims V8 does a better job of managing pointers and handling incremental garbage collections than its rivals. V8 has its own API so that it can be used in other browsers or programs.

Chrome uses multiple processes in which each process has its own dedicated memory and copy of global data structures. Google claims the approach requires more memory up front, but ultimately eliminates memory fragmentation which can eat up more memory in prolonged use of single-threaded browsers.

Separate browser pages called tabs are each run as a separate process so that one bad Web page will not bring down the whole browser. Each Chrome process has a fixed memory allocation that Google did not specify. A Chrome process manager lets users see how much memory and processor resources a given tab is using.

Webkit rendering
Chrome uses the open-source Webkit Web page rendering engine also adopted in Google's Android handheld software now in a beta release. Google said it also chose Webkit because it can be easily adapted for embedded systems, suggesting the company is interested in using Chrome beyond the PC.

In terms of security, processes cannot write to a hard drive or user files to prevent the spread of malware. Chrome uses a two-level security approach, running processes in a sandbox separate from a user mode.

Google called for industry standards for browser plug-in applications that can be run in a sandbox with reduced privileges. Currently plug-ins can run on the OS outside the browser.

In terms of privacy, users can open a private tab in Chrome that does not log history or cookies.

High security
Google uses its Internet savvy for some features in Chrome. The browser warns users when they are planning to access sites Google has previously identified as involved in trying to steal private user information, known as phishing. The company has created a public API to let others access the latest listing of phishing sites Google tracks.

In addition to tracking sites a user has previously visited, the browser also taps the Google service to recommend popular sites the user might like based on browsing patterns.

Google will publish an API called Gears to let developers share features it has built into the browser. No details about the API were immediately available.

The company claims it has tested Chrome on millions of the most popular pages each week.

- Rick Merritt
EE Times