On Tue, 2011-09-27 at 02:43 +0200, Bictor Man wrote: > thanks for your replies. indeed the filesystem caching seems to be the > difference. sadly I can't add more memory and the 6GB/20core combination > doesn't work. so I'll just try to tweak it as much as I can.
A (better) alternative to more memory is a SSD. Since they are 100 times faster than spinning drives for random I/O, the cache-miss penalty is much lower. Consequently free mem for OS cache does not matter as much and warm up requirements are lowered.
