You probably know that most of the data in our computers is saved to magnetic media hard drives that have spinning disks inside. The disk has delays as the read heads must wait for the disk to rotate the wanted data under the read/write heads. It can take the heads 4 to 12ms to find the data. Then the data can only be read as fast as the next bit of data comes to the read/write head.
Newer solid state drives (SSD) have no moving parts. So, there is no delay waiting for disks and/or read/write heads to rotate into position. So, rather than waiting several milliseconds the data is available in less than a millisecond. If you put your Second Life cache on an SSD, you will have a faster more responsive cache… places you have previously visited will render faster.
While conventional hard drives are cheap and can store terabytes of data on a single drive, the SSD’s are expensive. The cost per gigabyte of storage is about 100 times more than for conventional hard drives.
Also, while hard drives typically last 5 years or longer SSD’s have a life time that is shortened by use. Depending on whom one talks to life expectancy is 1 to 10 years, with 1 to 2 being more commonly stated. Manufactures hype longer life. We are finding out and I expect many current SSD’s to have a shorter life than expected. Only time will tell. But, as the technology develops they are living longer and getting cheaper. For now the tech is new and you know what that means: unexpected problems.
As SSD’s fill up they get slower… still faster than hard disks. Windows 7 and 8 have features to handle TRIM, which keeps the SSD cleaned up. If you use an SSD then you need to learn about TRIM.
An even faster and longer lasting solution is to use the computer’s memory as an SSD. We call this use of the computer’s Random Access Memory (RAM) a RAM Drive. You can see where one person benchmarked the speed difference here: SSD-vs-RAMdisk. While it took the SSD 0.6ms to get data the RAM Drive delivered it in 0.01ms.
Computer memory is designed for speed, reliability, and lots of read/writes. Its disadvantage is it only works and remembers things when power is supplied. Turn of the computer and the memory clears. But, RAMDisks are old tech and various ways to preserve the data on a RAMDisk have been devised.
So, for the fastest cache for Second Life using computer memory for a RAM Drive is a good, cheap solution.
Trinity Dejavu, with Catznip Viewer, has provided a tutorial on setting up a RAM Drive for Windows users. See: Speeding up SL with a RAMDisk.