Gentoo Archives: gentoo-user

From: Lord Sauron <lordsauronthegreat@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [OT] Re: [gentoo-user] Intel Core Duo Processor - Anyone?
Date: Fri, 31 Mar 2006 19:29:24
Message-Id: e5a3e9ac0603311117r66c1a8dfx4b9ebe3568b298fd@mail.gmail.com
In Reply to: Re: [OT] Re: [gentoo-user] Intel Core Duo Processor - Anyone? by Mike Myers
1 On 3/30/06, Mike Myers <fluffymikey@×××××.com> wrote:
2 > Just my .02c, but it seems like the 64-bit processors come with more
3 > hype than benefits. Not that the 64-bit move is a bad thing at all,
4 > but I mean it just seems like people tend to expect much more out of
5 > them than what they should.
6
7 You're very close to the mark, actually.
8
9 > It would seem like a more accurate, but oversimplified explaination
10 > would be that it simply allows for other improvements within the
11 > computer, but it does not improve anything on it's own. For instance,
12
13 Yes, you're very close. It does allow for one major thing OTTOH.
14 With a 64-bit wide word, more precise calculations take half the time
15 they would on a 32-bit chip. They don't give any other real major
16 64-bit exclusive benefits though. The advantages of a 64-bit variable
17 isn't really relevant for most uses though. Things like MatLab are
18 greatly benefitted, however, normal desktop use isn't. Some video
19 games are now being made 64-bit, so they'll benefit from more precise
20 gameplay at higher speeds, however, you are right: 64-bit en se
21 doesn't give any other amazing benefit.
22
23 > allowing >4GB ram, which in turn gives better performance. From what
24 > I've read, there are improvements in certain things that are specific
25 > to number crunching, like a database with mathematical formulas.
26
27 Yup.
28
29 > However, for a desktop processor, the difference is going to be barely
30 > noticeable, if any, especially since most desktops don't use more than
31 > 4 gigs of ram.
32
33 True. However, sticking to 32-bit for the rest of forever isn't a
34 terribly good idea, now is it?
35
36 > It definitely seems to be a difficult thing to explain though due to
37 > the nature of the processor. Most people think simply 'more numbers =
38 > more speed', but that's not really case, and surely not the point.
39 > Since around the mid 90's, processor speeds have steadily increased,
40 > but in the last couple of years, that increase has halted.
41
42 Not really. AMD is still making their chips more efficient and
43 faster, though the new fad is to add more cores. However, eventually
44 this will still limit threads to the speed of one core, which'll
45 prompt more and more rapid speed increases. Just be patient; you
46 don't need all that number-crunching power right now, do you? ; )
47
48 > Supposedly, the speeds have been maxed out for the size of the
49 > processors, so that's why the manufacturers are trying different
50 > routes, like hyperthreading, dual core, multi-core, and 64-bit. None
51
52 Well, they also need to make the thing smaller. We're still on what?
53 95 nanometre? Smaller means more transistors in the same area.
54
55 > of these features directly improve performance, but they do increase
56 > it's capabilities. More specifically, they allow the computer to do
57 > MORE tasks better, instead of focusing on speeding up tasks. That's
58 > not a bad thing really, because it's nice to be able to do multiple
59 > things simultaneously, like burning a cd while listening to mp3s and
60 > playing games on a LAMP server that's running emerge -u world without
61 > any degradation in performance in any of the processes.
62
63 People who do that scare me.
64
65 > That kind of performance seems to be what is intended with these
66 > different avenues that the chip makers are taking. That is not to say
67 > that single tasks will perform any better, and I think the lack of
68 > discerning the difference is causing a lot of confusion for most
69 > people, especially when they aren't familiar with low level
70 > programming.
71
72 In the end this might degenerate to a "programmer's rating" thing.
73 IE: one standardised benchmark.
74
75 > On 3/29/06, Richard Fish <bigfish@××××××××××.org> wrote:
76 > > On 3/29/06, Lord Sauron <lordsauronthegreat@×××××.com> wrote:
77 > > > www.alienware.com I beg to differ. I could have sworn I saw a laptop
78 > > > with more than 2G... where was it... wow! You appear to be right!
79 > > > Darn.. I could have SWORN I saw something with > 2G...
80 > >
81 > > Actually, you are right. I neglected the monstrous Clevo laptop. Its
82 > > an AMD X2 with capacity for 2 optical drives plus 2 hard drives, up to
83 > > 3G of memory, and a 200W power adapter. Weighs 12-15 lbs, _not_
84 > > counting the power adapter! This is acutally a Clevo design, sold by
85 > > Sager, AGearnotebooks, and many others. Alienware got it with a
86 > > customized case. All of the reviews I read on it basically said
87 > > "incredible performance, excellent display, but heavy, noisy, and
88 > > really hard to describe how large it really is".
89 > >
90 > > I was actually considering purchasing this beast...but the noise
91 > > factor scared me off. Not really appropriate for a shared office or
92 > > conference room.
93 > >
94 > > > compiler helps with the 64-bit part. It gets a bit technical, but
95 > > > there is a big difference between something made from the ground up as
96 > > > 64-bit versus something that was made 32-bit and just recompiled
97 > > > 64-bit.
98 > >
99 > > For most applications, this is not true. The vast majority of C/C++
100 > > code that runs on a desktop system couldn't care less whether longs
101 > > and pointers are 32-bits or 64-bits in size. It is a compiler
102 > > function to deal with that. And it is also a compiler function to
103 > > determine whether 64-bit or 32-bit registers should be used for a
104 > > particular operation. FYI, gcc has supported non-x86 64-bit CPUs for
105 > > a long time, so gcc's 64-bit support is probably more mature than you
106 > > think. So are the applications...many open source applications were
107 > > ported and adapted (if necessary) to 64-bit sparc and alpha processors
108 > > back in the late 90s.
109 > >
110 > > There are opportunities for some programs to take advantage of special
111 > > processor operations through assembly instructions. This is very
112 > > similar to how 3Dnow, MMX, SSE, et. al. make programs faster. So
113 > > there may be some specific optimizations for some operations that can
114 > > be improved over time.
115 > >
116 > > An example of an application domain that could benefit from 64-bit is
117 > > encryption, because for key setups you need to calculate very large
118 > > numbers. Such numbers could be calculated about twice as fast with
119 > > 64-bit operations vs 32-bit. *BUT*, this does almost nothing for the
120 > > actual data encryption itself.
121 > >
122 > > A good resource on the 64-bit vs 32-bit issues is to look at AMDs
123 > > optimization guide for software developers. Chapter 3 is particularly
124 > > relevant:
125 > >
126 > > http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25112.PDF
127 > >
128 > > -Richard
129 > >
130 > > --
131 > > gentoo-user@g.o mailing list
132 > >
133 > >
134 >
135 >
136 > --
137 > Mike Myers
138 > mike@××××.us
139 > http://www.yaay.us
140 >
141 > --
142 > gentoo-user@g.o mailing list
143 >
144 >
145
146
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