On 06/14/2013 05:38 AM, Amos Jeffries wrote: > So fast GHz ratings CPUs are better than more slower cores. That depends on the difference in CPU speeds, of course. If you are getting a reasonably fast modern CPU and want to maximize overall performance on a fixed budget, then getting more [physical] cores rather than getting the absolute fastest core on the market is often the right approach. Roughly speaking, Squid consumes X CPU cycles per transaction. You can double the load Squid can handle by doubling the number of cores or by doubling the speed of each core. In many cases, the former is cheaper than the latter. For example, two 2.6Ghz CPU cores are going to be better than a similar one 3.6GHz CPU core in most cases. You need to find the optimal combination of CPU speed and the number of cores for the budget you have. Assume linear scale with the total CPU speed (core speed multiplied by the number of cores). If you are lucky, the decision will be obvious, and the large difference between 1st and 2nd best options will eliminate problems associated with unrealistic assumptions such as linear scale. Please note that if you plan on using disk caching, dedicating one CPU core to each disk spindle is often a good idea (up to a point where individual disks become semi-idle because you have too many of them). With 125Mbps bandwidth, one CPU core should probably be dedicated to NIC interrupt processing and other OS needs. $0.02, Alex.
