64bit vs 32bit software

Thanks for the test Tom. That's not surprising to me.

The thing is with 64-bit software is while the processor fetches and works with 64-bit numbers, the applications usually just waste the extra space.

For example, if you declare a variable in a program to store an integer, it now takes 64 bits to store what used to take 32. Both take the same number of processor cycles to work with the number. What 64-bit allows is storage of a much larger integer (which for most things isn't needed) and for larger addressing (which is the most important 64-bit feature).

For the reason mentioned above, 64-bit applications will use more memory.

Basically, when you need 64-bit, you need it. When you don't it isn't that important.

Calibre was a poor example. Processing eBooks is a trivial task for any PC. Another program that I use is Handbrake to transcode video files. It is also available in 32bit or 64bit. I downloaded the latest version of each and did a test. I transcoded a 4GB avi mpeg-2 file to an mp4 file. I used the default settings for both tests. The resulting mp4 was 400MB. It took 11m 25s for the 32bit version and 10m 57s for the 64bit version. My PC is a 5 year old Toshiba Portege notebook with an i5 processor and 4GB of RAM. OS is Win 7 64bit. The 4GB of RAM is certainly a limiting factor, but I would of thought there would have been a bigger difference.

As a Calibre user I would consider it a non-issue for that app, as the program doesn't load all your books into memory at the same time, and there is not a whole lot of high bandwidth processing going on, even if you are doing format changes. I'm assuming you are not trying to catalog 30,000 books.

If you are capturing, decoding and encoding video, particularly HD or 4K video, then you might prefer the bandwidth of the 64-bit version of your video application. In another line, for image processing and cataloging, some of the processing tools run faster on 64-bit versions, and for catalog maintenance, being able to handle a catalog 2-billion times larger might make a difference if you have a lot of image files.

But comparatively, the largest books ever written are tiny, not really a 64-bit addressing problem.

GordonThree wrote:

Gdetrailer wrote:


Additionally with 64bit OS requirement you WILL need MORE memory.. 32bit Windows OS memory access STOPS at 3.2 GB of RAM, it cannot see or use any more memory above 3.2 GB..

IF you're still running Windows XP this is true. Vista and forward can access beyond 4gb even as 32bit. The limitation is, a 32bit application can only access one 4gb table at a time. Multiple applications can therefore make use of more than 4gb even with a 32bit OS.

Actually, the 3.2 GB RAM "limitation" IS still "there" but Vista and above have a " software work around" for the additional .8 GB that allows some limited access and use.. BUT, it IS LESS THAN IDEAL..

The 3.2 GB limit IS due to the 32 bit MEMORY ADDRESSING that comes into play, 64 bit OS versions have more memory addresses to work with.

XP did not have the software workaround so therefore 3.2 GB IS a hard limit..

But in reality even Vista and above will not make much of any real "use" of the additional .8 GB of the software workaround in a 32bit OS.

Gdetrailer wrote:


Additionally with 64bit OS requirement you WILL need MORE memory.. 32bit Windows OS memory access STOPS at 3.2 GB of RAM, it cannot see or use any more memory above 3.2 GB..

IF you're still running Windows XP this is true. Vista and forward can access beyond 4gb even as 32bit. The limitation is, a 32bit application can only access one 4gb table at a time. Multiple applications can therefore make use of more than 4gb even with a 32bit OS.

SCClockDr wrote:

Tom_M wrote:
Some software is available in either 64bit or 32bit. An example is Calibre eBook manager. Other than the ability to access more memory using 64bit, is there any advantage using 64bit?

64bit uses the full memory buss bandwidth thus processes at a greater speed. Threading is also improved with 64bit.

It depends.

IN MOST CASES there is very little "advantage" at all speed wise between the two. Only extremely complex operations will see any appreciable benefit (IE HD video editing/conversions or high res picture editing)..

eBooks, not so much.. They are designed to be pretty low impact and low bandwidth..

BUT, keep in mind, in order to be able to use 64bit software, you MUST be running a 64bit version of OS!.. You cannot run 64bit programs on a 32bit OS..

You can, however run 32 bit software on 64bit OS versions..

Additionally with 64bit OS requirement you WILL need MORE memory.. 32bit Windows OS memory access STOPS at 3.2 GB of RAM, it cannot see or use any more memory above 3.2 GB..

64bit Windows OS can access more than 3.2 GB and works much better with 8 GB or 16 GB..

If you do want to use 64 bit programs you need to check your OS version to make sure it IS 64 bit..

Tom unless you want to transcribe a whole bunch of ebooks from epub or rtf to another format as a batch job

You really won't notice the difference between 32 bit vs 64 bit

It's somewhat like the difference between a two lane hwy and a four lane.
You can't go faster but you can cram in more data at that same speed... sorta.

Average user likely won't see much difference. Somebody who does a lot of work with photos, video, or music/sound will see improvements in performance.

There is very little difference an "average" user will see between the two. Right now the processor in your computer is optimized to execute both 32 and 64 bit code equally well.

For the programmer, 64 bit allows access to higher memory registers natively, without having to use a "trick" interface provided by the CPU to use ram beyond 4GB.

If you're playing a large online game, it might run better as 64 bit because it needs a large contiguous block of ram.

If you're working on a mailing list with tens of millions of members, it might run better as 64 bit for the same reasons.

Eventually Microsoft and Intel will retire 32 bit, same as they did for 8 and 16 bit. That is a long way off.