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Regarding Mark Russinovich's technically detailed and otherwise excellent article Internals: "The Memory-Optimization Hoax" (January 2004, http://www.winnetmag.com, InstantDoc ID 41095), which debunks memory "optimization" utilities, I have just one comment: Free memory is the enemy of true performance.
This statement might strike many computer users as ridiculous, but with explanation it makes sense. Mark's article touches on this concept but then buries it under technicalities. If my OS isn't using all its memory, it's not using my machine to full capacity. Yes, a small portion of memory must remain unallocated to give the system room to work in, but all the rest of the memory should be used. I'm not referring to a situation such as running the system at near-maximum capacity and filling the entire virtual memory subsystem with a data set. I'm referring to modern, lightly loaded systems with large amounts of excess physical RAM that under usual circumstances will never be completely used. Ideally, the OS should use such excess RAM for caching, reallocating it only as needed. If the OS aggressively frees memory for some unknown future need, then data that the OS could have retrieved from RAM will instead require a disk read, incurring a massive performance penalty.
I became aware of this counterintuitive concept when I began to use FreeBSD. I learned from a Usenet thread that near 100 percent memory usage is not only "normal" but indicative of a properly working system. Now, I measure an OS not only by how much memory it keeps free but also by how much it uses. I realize that the situation is a bit more complicated than I've described, but my point is that free memory is not your friend. You paid good money for your RAM. Do you really want it to be unused?
—Henry Mason
hmason@dbsinet.com
I agree that an OS's job is to give memory to processes running on a system so that the processes can run efficiently and that this job requires using all physical memory. However, as I stated in my article, the Windows Memory Manager allocates memory by effectively using all "free" memory for cached file data, which the standby list stores. The Memory Manager uses this system to assign to certain processes only the memory they actually need so that other processes can get the memory that they actually need. One way the Memory Manager accomplishes this goal is by taking memory away from a process that doesn't need it and placing the unneeded memory on the standby list. If that process requests data from the standby list, it receives the data immediately; however, the memory demands of other processes might require that they also take memory from the standby list. The standby list serves as the file-system and paging-file cache, and even though memory on the list is considered "available," it's nevertheless actively used and therefore doesn't fit Henry's definition of free memory.
—Mark Russinovich
SBS 2003
I'm disappointed with Michael Otey's article "SBS 2003 Overview" (December 2003, http://www.winnetmag.com, InstantDoc ID 40708). The author doesn't seem overly familiar with Microsoft Small Business Server (SBS) 2003 and the way it works. First, he states that you can configure the Exchange POP3 connector to retrieve email from Hotmail.com and MSN.com. Aside from the fact that Hotmail.com and MSN.com are one and the same, you can't use POP3 to retrieve email from these types of Web-based email services. These services want you to have to go to their site to read your email so that they can present you with advertising. Otherwise, what's the point of offering free email services?
Second, the article omits mentioning Terminal Services in SBS 2003. The version of Windows Server 2003 that comes with SBS 2003 won't go into application mode. I've confirmed this fact with Microsoft and have experienced it firsthand. Windows 2003 in SBS 2003 will work in admin mode, but the function is restricted to two users with Administrator rights. Microsoft wants you to purchase a second server, with a second Windows 2003 license, to run Terminal Services in SBS 2003. This is a major "gotcha" in SBS 2003 and not a well-known one. Microsoft justifies this requirement as being necessary for security because the SBS server is a domain controller (DC). However, you can switch any other Windows 2003 server that's also a DC into application mode. In my opinion, this restriction in SBS 2003 is unfair. Many small businesses are interested in remote access. Given that SBS 2003 is targeted at the Value Added Resellers (VARs) and Value Added Providers (VAPs) that support these small businesses, those VARs and VAPs should be making the decisions about what is or isn't secure in an SBS 2003 installation.
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