If you recalculate something, so that the something doesn't stay in memory, it won't stay in the cache either. The cache is a memory cache - what's there is also in the main memory.

CPU's have become faster, but main memories have become bigger. Nowadays, computers tend not to swap; if your server swaps on a regular basis, you might want to do some tuning. Memory I/O is faster than disk I/0, and the ratio memory I/0 / disk I/0 is more than the ratio cache / memory. I/0.

Maybe not much of a data point, but from the servers with resource problems I've seen, more of them benefitted from getting more memory, than more or faster CPUs. Most computers have more than enough CPU cycles - but usually they can use more main memory.

Abigail

In reply to Re: Out-Of-Date Optimizations? New Idioms? RAM vs. CPU by Abigail-II
in thread Out-Of-Date Optimizations? New Idioms? RAM vs. CPU by liz

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