I am testing disk I/O performance on a server of mine, which will eventually run Postgresql. I am following this web site to perform my benchmarks.
The benchmark consists of running
dd and reading/writing N blocks the size of 8k (which is the size of blocks Postgresql uses). N is to be calculated as follows:
N = 250,000 * gigabytes of RAM
So, I have 16GB of ram, which gives me 4 million blocks to read/write. That is fine, but...
I am unsure where the magical number of 250,000 comes from?