Primo Ramdisk and PrimoCache are two software programs which both utilize physical memory to reduce file access time and speed up computers. However, they are two different types of program and have different focuses. They both have pros and cons compared with each other. Besides, they are independent of each other, and you may install one of them, or both, depending on your needs.
Primo Ramdisk is a simulator program which creates virtual hard disks by using memory. All Windows read and write requests to virtual disks are done in memory without accessing physical disks.
PrimoCache is a cache software program which creates an additional filter layer onto disk storage layer and intercepts Windows read and write requests to disk. If disk data being requested already exists in the cache, PrimoCache serves the request by simply reading its cache. Otherwise PrimoCache fetches data from the disk and store it into the cache, then completes the request.
As per the summary of pros and cons above, Primo Ramdisk and PrimoCache have different usage focuses. In general, because PrimoCache is transparent to applications and there is no limit on memory amount, PrimoCache is able to work in most scenarios. Usually it is preferred in scenarios where handiness and simplicity is a prime consideration or system does not have enough memory. In contrast, Primo Ramdisk is preferred in scenarios where performance is the main focus and system has enough memory. These scenarios include but not limited to:
Let's take a look at an example scenario that will tell the usage difference between Primo Ramdisk and PrimoCache. In this example, the goal is to improve the running speed of frequently used applications. One way to achieve this goal is to install these applications on a ramdisk which enables the image file feature. During computer boots-up, ramdisk loads the image file which contains installed application files to the memory. Thus these applications are ready to run completely in memory, which will show a very fast startup and running speed. Though this way will increase the computer boot time, it is worth. This is because Primo Ramdisk loads the image file with large sequential read. Considering that large sequential read is much faster than random small read, the image file load time is much less than the total time taken to read out all applications one by one. Besides, computer boot time is not a consideration in some scenarios.
The way described above is able to get the best performance. However, it is not suitable if you have already installed these applications on physical disks and wouldn't like to change, or if system does not have enough memory to store all application files. In such situations, PrimoCache becomes a better choice.