The following requirements apply to all current PixInsight versions.
PixInsight is available for 64-bit machines supporting the x86_64 / EM64T architectures: Intel Core Duo, Intel Core i5, Intel Core i7, Intel Xeon, AMD 64, etc.
All 32-bit versions of PixInsight are now officially obsolete. The current version 1.8.0 of PixInsight is only available as a 64-bit application on FreeBSD, Linux and Mac OS X. A 32-bit Windows version is still being released for compatibility with legacy hardware and operating systems, but it is not supported and will be discontinued during 2013.
The PixInsight platform has been ported to the FreeBSD, Linux, Apple Mac OS X and Microsoft Windows operating systems. The primary development platform for PixInsight 1.8.0 is Fedora 16 Linux on x86_64 workstations.
PixInsight 1.8.0 for Linux requires glibc version 2.15 (March 2012) and a 64-bit Linux distribution.
PixInsight is not compatible with Mac OS X 10.5 (Leopard). It requires at least Mac OS X 10.6 (Snow Leopard). If you are still using Mac OS X 10.5 on your machine, the obvious solution is installing OS X 10.6 (or 10.8). It's more secure and efficient, and is a real 64-bit operating system (10.5 uses a 32-bit kernel).
Windows XP is not supported. The PixInsight Core application runs on Windows XP, but there are screen rendering problems and, which is more important, our automatic updates system does not work correctly on Windows XP. Our updates system is based on UAC technology (User Account Control) and code signing, which unfortunately are not available on Windows XP.
PixInsight does not run on Windows NT, 2000, ME, 98, 95, or 3.1x/Win32s.
The PixInsight platform will use all processors and processor cores available on your machine. We strongly recommend using PixInsight on a quad-core or six-core processor.
Under 32-bit Windows (obsolete, unsupported), PixInsight is able to address memory beyond the 2 GB barrier, Windows permitting. On 32-bit Windows, we recommend our users to edit the BOOT.INI system file to add the /3GB parameter. This will free more memory that will be available to applications. Refer to your operating system documentation.
There are no 32-bit versions of PixInsight for UNIX/Linux and Mac OS X since version 1.8.0.
64-bit versions of PixInsight have no practical memory limit. They will use all memory available to applications, and will allocate virtual memory on disk when necessary.
We strongly recommend a high-end 27-inch or larger LED/LCD panel, or two panels driven by a dual-head video card. For serious image processing, working with large monitors is a real must with PixInsight.
On X11 (FreeBSD and Linux) a compositing extension manager is required. Hardware-based compositing, such as OpenGL, is a precondition to run PixInsight on all platforms, including X11. As an exception, the KDE desktop environment allows you to use software-based compositing (XRender) on systems without hardware acceleration. XRender compositing works fine, but is slow. However, XRender allows you to run PixInsight on a virtual machine where the virtualization system does not provide video hardware acceleration.
To work with two or more monitors on FreeBSD and Linux you must have the Xinerama X11 extension installed and correctly configured (this should work out-of-the-box with modern X11 desktops).
To maximize availability of RAM for critical tasks, the processing history management and masking systems implemented in PixInsight are based on temporary disk swap files. In addition, more space is required during file writing operations, due to disk I/O security strategies (basically, when an existing file is rewritten a temporary copy of the original is kept during the whole disk write operation).
We really cannot speak of a minimum required free disk space, since this depends on the number and dimensions of the images that the user opens and modifies in the application. PixInsight is able to store and manipulate seven different sample formats transparently: 8, 16 and 32-bit integers, along with 32 and 64-bit real and complex floating point. 32-bit and 64-bit images require two and four times more disk storage space, respectively, than the native 16-bit format of a CCD camera. In addition, PixInsight can store an unlimited number of history states (unlimited undo/redo operations). This makes PixInsight Core a demanding application regarding free disk space requirements. For serious production work, we recommend a minimum of 50 to 200 GB of free hard disk space, depending on the average size of your images and the complexity of your processing workflows.
PixInsight demands fast hard disks. We recommend working with last-generation Serial ATA disks or, much better, high-throughput SCSI and SAS disks, or solid-state disks.
Under Windows, disk fragmentation may affect performance severely. You should always keep the information reasonably compacted on your hard disks by running the Windows defrag utility frequently, or any suitable disk maintenance utility. This is true for both the NTFS and FAT32 file systems.
The native file systems of these operating systems (ext3, ext4, xfs, zfs, hpfs) have minimal fragmentation problems thanks to their design. Fragmentation on a typical Linux or Mac OS X disk is very low no matter how much file system activity occurs. There is no need for a defragmentation utility on FreeBSD, Linux and Mac OS X.
Starting from version 1.4, PixInsight uses parallel disk I/O operations to generate and maintain temporary swap disk files. When two or more physical disk drives are available, PixInsight can be configured to spread swap files on all disks (no specific limit), and read/write them through parallel execution threads running concurrently.
The performance gain that can be achieved thanks to parallel disk I/O in PixInsight can be spectacular. For example, with just two Serial ATA 300 disks (not particularly fast drives), PixInsight can easily achieve data transfer rates above 500 and 140 MB/s, respectively for read and write operations. This allows working with huge images in PixInsight. For example, with four fast drives configured for parallel swap file storage, you can work with a 32-bit RGB image of 12000×12000 pixels and perform undo/redo operations virtually in real time. Note that parallel disk access is at least as fast as—and much easier to configure and maintain than—RAID 0 storage.