Some loads will benefit from having more threads running, whereas some will benefit from having a smaller number of faster processors. Basically, if you are becoming CPU bound, then scaling up will most likely help you out more than scaling out. Research has shown that two CPUs will not generally be as fast as a single CPU with twice the clock speed, at least not on an app by app basis. Cache can also make a huge difference in the performance of a given processor. Getting a processor with a large L2 or L3 cache will generally provide better performance than a simple jump in clock speed.
You guessed it, more cache. Recommending RAM is a bit of a two-edged sword. Problem is, recommending how much RAM to use is really nothing more than an educated guess. So, the trick is to install enough RAM so you never really deplete it all, while still having as little left over as you can. Obviously, a comprehensive performance baseline is out of the scope for this post, but a good rule of thumb is to simply monitor Working Set with Perfmon.
Application recommendations are of course going to trump any ad hoc testing you may do. If a vendor says you need X amount of RAM, it is best to install at least that much just to be on the safe side.
The pagefile is the other piece of virtual memory that we need to be concerned about. The pagefile is really just a file on the hard disk that is set up so that it operates like RAM. Problem is, RAM is fast and hard disks are slow. So, having to read or write to the hard disk when the system needs to satisfy a memory request can be very time consuming.
To speed access to the paging file, it is recommended to place it on a separate physical disk than the operating system. Better yet, create multiple paging files on different disks, or even on multi-disk arrays for real speed.
Withdrawn products : This books describes products that are no longer sold by Lenovo. Part 1. Introduction Chapter 1. Introduction to this book Chapter 2. Understanding server types Chapter 3. Performance benchmarks for servers Part 2. Server subsystems Chapter 4. Introduction to hardware technology Chapter 5. Energy efficiency Chapter 6. Processors and cache subsystem Chapter 7. Virtualization hardware assists Chapter 8. PCI bus subsystem Chapter 9.
Chipset architecture Chapter Memory subsystem Chapter Disk subsystem Chapter Network subsystem Part 3. Operating systems Chapter Microsoft Windows Server Chapter Linux Chapter VMware ESX 3. Monitoring tools Chapter Windows tools Chapter Linux tools Chapter
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