We get the impression that going to the Cloud means signing up and getting the payment and login details. Of course this is false. We have no end of articles telling us about teething problems, or being better off with hybrid or private or public cloud or anything other than what we had before. But there are still more things to consider, and that means wading through a lot of figures and making a few worrying decisions. And actual experience might change a few decisions and opinions too.
The speed will vary according to which cloud server that you use, both the company and the options within that company. Bigger machines can be slower, and the reasons for this vary. This is complicated further by the fact that different test programs can run quickly in some situations but less quickly in others, and not run at all in the case of some servers who aren’t set for that particular software.
It would make sense if the more expensive services were faster, or had some other advantage; but this is not always the case. More CPU’s will be faster, all else being equal, but while 8 CPU’s will be faster than One they are unlikely to be 8 times as fast. Windows Azure machines were more than twice as fast when they used the 8 CPU’s option instead of one, but that doubling of speed came at 8 times the cost.
If you increase the number of CPU’s but keep the same amount of RAM you might save some cost. But this can affect the performance in unpredictable ways. Sometimes a 2 CPU Machine is faster than a single CPU machine with the same RAM, but not by a large amount (perhaps 30%). Sometime the 2 CPU is actually slower.
Google Cloud seems to have a fair way of tallying their performance with price, so that their expensive options do have significantly better performance. How that compares to the options offered by another company is another matter.
To make matters more confusing the performance varies over time even with the same system and provider. If you’re using Cloud you are sharing resources with other users, because that’s what Cloud is about. If a lot of computing power is being used by a lot of other groups, then you don’t get any special consideration; things will be slower. Occasionally this works to your advantage and you get bursts of high speed interaction, but only at off peak usage times. If you only want lots of computing power for short periods of time this might be fine. Constant usage, however, will probably mean fluctuating speeds.
Fluctuating Cloud speed might make a smaller provider more attractive, or a super large provider with greater resources; but you need a lot of CPU’s and RAM to achieve significantly higher speeds. Even then it’s had to know which option is best, as speed still varies with the application, and will fluctuate with user traffic. You can’t know these things till you (or somebody else) has tried the service, and even then it might degrade if they accumulate more clients, or improve when they decide to upgrade.