You're trying to evade the issue. (The issue being whether designing a 128 bit filesystem today is reasonable or completely over-the-top.) I'll respond only to the one relevant bit of your response.Well Steve. First of all, I have studied more math than you ever had, which is evident because you say so ignorant things. Second, I suggest you read a bit more. You know, the hype about ZFS and DTrace, etc - is for real. The Solaris guys ARE good. They KNOW what they are doing. Otherwise noone would cared for ZFS nor DTrace. When the Solaris guys says things, you better listen. They know things. You DONT. They can see trends, they know how much storage the server halls are bying, and they see it grows exponentially. You dont have that information.
When you talk about Moore's law
"Moore's law is about transistor density on silicon. It has nothing to do with disk space."
Let us read more on this law, regarding hard drives part:
It turns out that hard drives have the same development, called Kryder's law:
"A similar law [as Moore's law] (sometimes called Kryder's Law) has held for hard disk storage cost per unit of information"
And there is a article in "Scientific American" about Kryder's law:
Which says that "says that magnetic disk areal storage density doubles annually"
Do you know enough math to understand what this means? It means EXPONENTIAL GROWTH, the same as Moore's law. And if you dont know theory about asymptotics, let me tell you. Exponential growth is a very bad thing, it grows extremely fast. It actually, grows exponentially. Therefore you are wrong on this. Your premise is false, and your entire reasoning is FAIL. And you say I dont understand arithmetic and math? Jesus. What are those Linux guys out there? Uneducated all of them? I cant help but wonder. Why am I wasting time pointing out errors in their juvenile reasonings?
Kryders' Law is demonstrably optimistic. In 1996, a Seagate ST225 20MB drive sold for about $229. (I remember because I bought one.) In the intervening 24 years, if Kryder's estimate were correct, we'd have 335TB drives on the shelves today. We don't. If instead, you assume that capacity has doubled every 18 months, it extrapolates about to about 1.4TB today. Clearly, viewed over the last 24 years, an 18 month doubling period is far more accurate than the "doubling annually" supposition. Then again, Kryder is talking about data per unit area, and drive areas have decreased. The important and relevant bit is that from a commercial standpoint, the cost per dollar has halved only about every 18 months. That, and the practical matter of "how many physical drives does it take to achieve X capacity", and not data per unit area, are the relevant points regarding.
But even if we assume that filesystem size requirements doubled annually, we're still looking at 32 years to grow from what 32 bit can support to what 64 bit can support. And another 64 years to go from what 64 bit can support to what 128 bit can support, for a total of 96 years. If we (*very* generously) assume that some apps today require 48 bits, (and can anyone cite an example of that?) that's still 80 years using your overly optimistic growth estimate. I ask again, do you really think people will be mkfs'ing new filesystems with ZFS in 80 years?!
In a nutshell... and just so we don't go too far off-track... my position is that ZFS is a fine filesystem for *Solaris, but wouldn't be a good fit for Linux even aside from the licensing issue. btrfs *is* a good fit for Linux. btrfs development is proceeding very well. And 128 bitness in a filesystem is just plain silly in 2010.