Jim,
Once you get the system you want, when setting up check back about setting up your preferences re swap files. I have found a ramdisk to really speed things up, and then I also point to several swap locations on SSDs (64Gb locations should be fine, though I use 128Gb folders). Check out this quote from Juan as a starter:
New Parallel Swap File Storage
To maximize availability of RAM for processing tasks, the processing history management and masking systems implemented in PixInsight are based on temporary disk swap files. Basically, a swap file is required at each processing step to store the previous image state, so you can undo/redo actions, carry out masking operations, and travel the processing histories of images arbitrarily.
When working with very large images, swap file access can be the most important bottleneck that compromises performance of the entire PixInsight platform. This is particularly relevant on 64-bit systems, where there is no practical limit to image sizes, which opens the door to really huge mosaics and high dynamic range stacks. Note that we are talking of disk swap files in the multi-gigabyte range.
Starting from version 1.4, PixInsight Standard 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 a set of physical disks (no specific limit), and read/write them through parallel threads executed 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 swap read and write operations. This allows working with very large 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 almost in real time. Note that parallel disk access is even faster —and much more flexible, easier to configure and implement— than RAID 0 storage.
To use parallel swap file access with PixInsight, you need two or more independent, physical disk drives. Do not try to enable this feature using several directories or disk partitions on the same drive, since multiple parallel write operations performed on a single hard disk may be dangerous to the integrity of the drive.
To enable parallel swap file access, select the Edit > Global Preferences main menu option. On the left panel of the Preferences interface, select the Directories and Network item. You can specify a list of folders for swap file storage. However, as we have said, only specify folders on independent physical disk drives.
Note that for a Ramdisk, you can point to the same location several times (I point to mine 4 times before pointing to the swap locations on the separate SSDs on my system).
Best,
Jim
