Gentoo Archives: gentoo-dev

From: Spider <spider@g.o>
To: gentoo-dev@g.o
Subject: Re: [gentoo-dev] GCC 3 Vs GCC 2 and some other stuff
Date: Sun, 07 Apr 2002 21:44:09
Message-Id: 20020408044612.4489e915.spider@gentoo.org
In Reply to: [gentoo-dev] GCC 3 Vs GCC 2 and some other stuff by Eugenia Loli-Queru
1 I know well that this is was completely unscientific and unreproductible
2 behaviour, with only one run and so on.
3
4 PDC20265: chipset revision 2
5 PDC20265: not 100% native mode: will probe irqs later
6 PDC20265: (U)DMA Burst Bit ENABLED Primary PCI Mode Secondary PCI Mode.
7 ide2: BM-DMA at 0x7400-0x7407, BIOS settings: hde:DMA, hdf:pio
8 ide3: BM-DMA at 0x7408-0x740f, BIOS settings: hdg:pio, hdh:pio
9
10 hde: Maxtor 5T030H3, ATA DISK drive
11 its an Athlon t-bird 1GHz
12 MemTotal: 288548 kB
13 (PC-100 SDRAM)
14
15 Filesystem on the drive used for compilations are ReiserFS.
16
17 Using r5 hash to sort names
18 ReiserFS version 3.6.25
19
20 also, the fact that I dont use the same compiler flags for both
21 compilers are a dead giveaway.
22
23 Better code, I can't speak for. More tests, I can, I've had to patch up
24 some c++ code in order to fit the stricter tests, something I consider
25 good.
26
27
28 cpu idle time doesn't matter much when diskaccess is ventured, should I
29 ever intend to do a good benchmark I'd use tmpfs for the whole process,
30 and make sure I dont run out of RAM while doing it. This is a user
31 comparsion, the feeling of how long things take to compile c++.
32
33 And yes, the machine was in "normal use" at the time. Xchat, sylpheed
34 and some aterm's. bad behaviour for a benchmarker. But standard for me
35 whenever I compile things, and thats how I wanted the comparsion done.
36
37 kernel is for once the default gentoo one, something I seldom use
38 normally. (I prefer -jam series)
39
40 //Spider
41
42
43
44 >
45 > So, regarding your benchmarks Spider. There is something wrong,
46 > definately. And I think our gentoo kernel heads around here should
47 > take a close look at it. Sure, GCC 3.X *is* slower on compilation
48 > time, however, your tests show a very disturbing fact: Under some
49 > circumstances, your CPU seems to spend unreasonable amount of time not
50 > doing anything. This could be an indication of a bigger issue,
51 > possibly a configuration or a hardware issue. There might be an issue
52 > going on with the cache or the filesystem or even the loader. How much
53 > memory the PC you used has and what kind of drive and filesystem did
54 > you use? (I hope that all this is not a side effect of one of the
55 > Gentoo kernel patches...)
56 >
57
58
59 --
60 begin happy99.exe
61 This is a .signature virus! Please copy me into your .signature!
62 See Microsoft KB Article Q265230 for more information.
63 end

Replies

Subject Author
Re: [gentoo-dev] GCC 3 Vs GCC 2 and some other stuff Stacey Keast <slik@×××××××××××.net>
Re: [gentoo-dev] GCC 3 Vs GCC 2 and some other stuff Bart Verwilst <verwilst@g.o>
Re: [gentoo-dev] GCC 3 Vs GCC 2 and some other stuff Geert Bevin <gbevin@××××.com>