Question

I just noticed that by instance famous application like chrome didn’t have any 64 versions at least under windows.

In my firm I write applications which run under 64 bits version of windows in 32 bits mode.

I am wondering if I could have some advantages/performance gain to build applications in 64 bits mode rather than in 32 bits

Edit :

Typically, in which kind of software, the increase of registers number will be benefict ?

Answer 1

64 (x86_64) bits is mainstream now.
2 big advantages here:

• Available more memory without any tricks
• More general-purpose and additional processor registers

But you have small disadvatage too:

• More memory consumption (usually like 20-30% bigger than 32 bit)

I think Google Chrome runs in 32 bit mode in Windows because there are too much 32 bit plugins (like Flash). Also there is linux version for 64 bit.

Edit for additional question

Typically you will get benefits if your application uses math (64-bit integer arithmetic), coding/encoding/packing/unpacking, cryptography.

Also look at IBM 64-Bit Computing Decision-Maker’s Guide
http://www.onitecservice.com.br/produtos/arquiv_pdf/nocona64bit_onitec_service.pdf

What types of applications will and won’t take advantage of the switch from 32-bit to 64-bit computing?

In order from greatest to least benefit, the types are:

• I/O intensive — Any application that spends more time fetching data from devices than
  processing it: database back-end, e-commerce, CRM, ERP, SAP, SAS, various business-critical and vertical applications, and any other application that has large memory requirements. In
  general these applications should see significant performance improvements from 64-bit
  hardware, operating systems and device drivers, as well as the elimination of memory
  overlays and other performance inhibitors.
• Compute-intensive — High Performance Computing (HPC) and scientific/technical
  computing, including life sciences, geophysical research; high-end graphics rendering;
  streaming video, and any other application that spends more of its time processing data than retrieving it.
• Gateway/security infrastructure — SSL servers, directory services, Internet caching and
  database front-ends. These applications may obtain benefit from the switch. You should
  contact the individual software vendors to find out their plans for exploiting 64-bit features.
• Standard infrastructure — This class generally will see little benefit from 64-bit computing. Applications include file and print servers, low-volume/noncritical business applications, and legacy applications that are unlikely to be rewritten for 64 bits.