Zoom Search Engine FAQ - 64bit support

The short summary

From the V5 release of Zoom, 64bit operating systems are supported. This applies to all editions, including the free edition of the software.

However since V6 you can get higher capacity on a 64bit O/S using the native 64bit version of the indexer (Enterprise edition only).

More detail

The Zoom software itself in V5 was 32bit only. But the operating systems, in general, provided full backward compatibility. So Zoom runs fine in 64bit operating systems.

From the V6 release of Zoom the indexer will now be available in both native 32bit and 64bit executables. The 32bit software is limited to using only 2GB of RAM, regardless of how much RAM was actually installed in the machine. This was a Window 32bit limitation. The native 64bit release of Zoom in V6 allows an almost unlimited amount of RAM to be used, if the RAM is physically available in the machine and you are running a 64bit O/S.

There is no functional difference between the 32bit and 64bit releases. They have an identical set of features. The only difference is in how much RAM they can use. Being able to access more RAM, means a higher potential capacity. But as the capacity of the 32bit release was around a million pages, only a few people will need to use the 64bit release. So the 64bit release will be made available as part of the Enterprise edition.

64bit scripts

There is no need to alter the ASP, PHP, Javascript or CGI scripts to support 64bit operating systems. The CGI's remain as 32bit executables. They don't use enough RAM to justify making a 64bit release, and the 32bit CGI's remain compatible with 64bit Windows and Linux. So there is no benefit to changing them.

When to use the 64bit indexer

You should only need to use the 64-bit Indexer if you have 64bit hardware, a 64bit operating system and meet one of the following conditions:

  1. You are indexing an enormous number of web pages or websites, and your individual index files are exceeding 2GB in size. The normal 32-bit Zoom Indexer will warn you when this happens.
  2. You are indexing an enormous number of web pages or websites, and you require more than 4GB of memory and you have more than 4GB of memory installed on your computer.

Note that there is no advantage to using the 64-bit Indexer unless one of the above criteria are met. Typically you would need to be indexing several hundred thousand pages before you would meet the conditions above. On the other hand there is no real disadvantage in using the 64bit indexer if you have it.

How to use the 64bit indexer

You can find the 64-bit version of the Zoom Indexer under the Start menu, in Zoom's Program folder.

Old Linux and large index files

If your web server is running older versions of Linux and BSD, you may find that it does not offer Large File Support (LFS). This means that it can not open or access any single file which is larger than 2GB in size. If you are indexing up towards a million pages or content which feature over a million unique words, then there is a good chance of hitting this limit. The CGI itself is designed to work with files larger than 2GB in size on any version of Linux and BSD which provide LFS. If you are not sure, check with your web host what version of Linux or BSD they have installed on your server and whether it features large file support. Upgrading the server to a newer version of Linux or BSD which feature LFS will address this problem. Any version of Unix or Linux released in the last 5 years should not have this problem.


Return to the Zoom Search Engine Support page