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  1. Re:I can't understand ECC on To ECC Or Not To ECC? · · Score: 3, Informative

    tzanger wrote:
    > It's my understanding that ECC works on the smallest data width available, which is 64 bits on SDRAM
    > anyway. When your P4/2.1G grabs a single byte and there's a cache miss, it fetches the entire row
    > (8 bytes) from RAM anyway. Block-based, yes, but no bigger than normal.

    Wrong. SDRAM is 64 bit wide, but can be written in units of 8 bit. A read is always 64 bit wide. A single 8 bit write to ECC RAM becomes a 64 bit read, check ECC, update byte to be written, recalculate ECC, write. So you are going to get a small speed penalty compared to the non ECC case of just a single 8 bit wide write.

  2. Re:I can't understand ECC on To ECC Or Not To ECC? · · Score: 3, Informative

    Because you turned off the ECC checking ....

    The idea with ECC is that the ECC controller (a peace of hardware between the CPU and the RAM) should detect the bit error and correct it "on the fly", so that the application should not be affected by the bit error at all. You get a speed penalty by doing ECC, because the ECC controller have to calculate a check sum for every write, and check the check sum for every read. Even worse, the ECC check sum is block based, so the ECC controller have to read the whole block to calculate the check sum even if the CPU only reads a single byte. The same goes for writes. To use ECC you need special RAM which is 72 bit wide instead of 64 bit, the extra bits are used for the check sum. This also explains why ECC RAM is more expensive that non ECC ram.

  3. Intertwingle on Text-Mining Your E-mail · · Score: 2

    jzw of Mozilla/Netscape fame have a hypothetical program called Intertwingle which is (Score:5,Interesting) ....

  4. Intel e1000 adapter on Mixing Gigabit, Copper, and Linux · · Score: 2

    There must be something wrong with the graphs for the e1000 packet size vs. throughput plot, I believe the axis are reversed.-

    Also Intel acknowledges that their e1000 adapter have driver issues under linux. This text is from: ftp://aiedownload.intel.com/df-support/2897/ENG/re adme.txt

    Known Issues
    ============
    Driver Hangs Under Heavy Traffic Loads


    Intel is aware that previously released e1000 drivers may hang under very
    specific types of heavy traffic loads. This version includes a workaround
    that resets the adapter automatically if a hang condition is detected. This
    workaround ensures network traffic flow is not affected when a hang occurs.

    This is for the driver verion 4.1.7, released 3/23/2002 (ie. quite new). Older versions had even bigger problems. This might explain why the Intel adapter does so bad in this test. I wish that Intel gets a clue and releases all card specs and GPLs the existing driver so that a true (stable) open source driver could be written and included in the linux kernel. I think the hardware is OK, but the drivers sucks.

  5. Re:RSA SecurID on Cross-platform Password Management? · · Score: 1

    Zeinfeld wrote:
    Look at the activecard tags, we switched to them because they are half the price of SecureID and more reliable to boot.

    Can these be used with Linux? I couldn't find any info on their web site (www.activcard.com ?)

  6. Postfix *and* vsftp on RedHat 7.3 beta (skipjack) is out · · Score: 3, Interesting

    Yes !!!

    postfix-1.1.4-3.i386.rpm

    vsftpd-1.0.1-4.i386.rpm

    I must be dreaming, postfix and vsftp in the next redhat. I am going to upgrade my servers to 7.3 when it is ready. Yes, definitely, yes, going to upgrade ...

  7. Remember to install a phone on Planning a Small Server Room · · Score: 5, Insightful

    The one thing I am missing in our server room is a plain phone....

  8. Re:Please release the source under GPL on NaN Closes Shop, The End of Blender? · · Score: 5, Informative
    Anonymous Coward wrote:
    >It's already GPLed, Einstien.

    Wrong.

    from Freshmeat:

    Per the license: "You are hereby granted permission to copy and distribute the Software without written agreement from NaN, only for non-commercial purposes."

    Other parts of the software, such as the blender render daemon, are fully Open Source and Free Software, released under the new BSD license.

  9. Re:Some info about the XScale processors here on Fujitsu Announces XScale PDA · · Score: 4, Informative

    Why not go directly to the source:

    http://developer.intel.com/design/intelxscale/

    Here is the info on the PXA250 CPU .

    You will find specs, datasheets and all the goodies.

  10. Technical explanation on how this works .... on Google Juice · · Score: 4, Interesting

    ... on slashdot !

  11. Secure Programming for Linux and Unix HOWTO on Building Secure Software · · Score: 5, Informative
  12. Re:A better idea .... on Carrot, an Open Source C++ scripting module for Apache · · Score: 2

    Yes but you are still stuck with code like:

    printf("<tr>\n");
    printf("<td colspan = \"2\">\n");
    printf("<img src=\"/img/myimage.png\" alt=\"comment\" border=\"0\" height=\"100\" width=\"150\">");

    Not very readable. We need a preprocessor which embeds the HTML code in C for readability.

  13. A better idea .... on Carrot, an Open Source C++ scripting module for Apache · · Score: 2

    I like C, but I think they got this the wrong way around...

    Instead of creating a scripting language out of C, they should have created a good way to embed html codes in the C source (eg. a pre-processor and a custom library), and compile the pages to a cgi program.

    This way you will get the best out of both worlds. You can code in C, and get real compile time checking instead of an interpreter failure because of a misspelled variable name or keyword. You get the speed of a compiled program and the C code can contain real html with no escape characters.

    With a good library (no libc by default, that is too risky ...) you can get access to apache internals, code in C (that is the whole idea, isn't it ?) and get super fast performance. The library needs a large collection of string handling functions.

  14. A year ago someone did this .... on Complete Filesystem Checkpointing? · · Score: 2

    It was called SnapFS. You can find traces of this in a LWN article. I don't know if the projects still exists, go ahead and google .....

  15. Many scanners don't scan .swf files on Even Flash Can Get Viruses · · Score: 5, Informative

    Many virus scanners don't scan .swf file by default, so you have update your virus signature file (which is automatic on most scanners) and reconfigure your scanner to scan .swf files (unless you already scan all files on your computer).

    This means that if advanced .swf viruses are created, they could become a real problem until system admins wakes up and gets a clue (and that takes a loooong time, look at Code Red)

  16. Re:The /var directory is in bad shape too on Rage Against the File System Standard · · Score: 2
    omega9 wrote:

    The parent poster, for example, is trying so hard to impress with his knowledge of the history of /var (available in pretty much any *nix book), yet fails miserably when it comes to understanding that there is no gun to his head forcing home to keep html in /var/www. I agree, I think /var/www is an odd place for html data, but there's always the option of changing your http root directory, moving it somewhere else and symlinking back to /var/www, or a few other options.

    I would agree with you, if it only was /var/www, but how about the complete postfix chroot environment in /var/spool/postfix (eg. /var/spool/postfix/etc/passwd ) ? What about the printer configuration files in /var/spool/lpd/{printer name}. What about the gdm faces in /var/gdm ? Heck, how about the compete RPM database in /var/lib/rpm ? This is all pollution of the /var hierarchy.

    In a follow up omega9 writes:

    Anyway the point of this post is just to mention that all distros that I'm aware of that use the /var/www directory for html data do not actually store it there. /var/www/html is a symlink to /usr/local/apache/htdocs by default.

    You are lucky, the only distro that I know well (RedHat) stores the html files in /var/www since RedHat 7.1. /var/www/html is a real directory. Which distros are you aware of ?

  17. The /var directory is in bad shape too on Rage Against the File System Standard · · Score: 2

    The /var directory used to be for files that are difficult to backup to tape, because they varies too much (*see* that's the reason for its name). A backup of /var used to be outdated after a few hours.

    The print spool, the incoming and outgoing mail spool, pid and lock files and the man file cache are all files that changes rapidly, and in general does not need to be backed up every day. You need a backup of its directory structure in case of a disk crash, but doing a complete backup every night used to be a waste of time.

    That is history. Now people wants to mount /usr read only, so they are slowly moving all files that must stay on a RW file system from /usr to /var (eg. /var/www for your web site). This is stupid, because you need to do a backup of some directories in /var but not all. The grand idea of /var is lost.

    Please stop this trend before it is too late.

  18. Brian Valentine on "Linux is *the* threat," Says Microsoft · · Score: 2
    This page contains Brian Valentines (the author of the leaked memo) bio:

    http://www.microsoft.com/presspass/exec/valentine/ default.asp

  19. Wietse Venema on Nominations Sought For Open Source Award · · Score: 4, Insightful

    My nomination for is Wietse Venema, the author of the postfix mail server.

    Why:

    Have a look at the source code, it is a textbook example of how a program should be written. It is just amazing how well the code is commented (all 100.000 lines of it), and Wietse is doing a fine job of maintaining the code. The program is well behaved (also in severe error conditions like out of memory/disk space, high cpu load, network failures, etc), and have an excellent reputation for being "virtually bug free" ...

    Postfix is simply the finest piece of software I have ever compiled and used, and I hope that the award goes a person because of his exceptionally high software standards: Wietse Venema.

  20. Re:Somewhat misleading on Linux Breaks 100 Petabyte Ceiling · · Score: 3, Interesting

    The glibc limits the file size to 64 bit (9 million terabytes), so unless the POSIX LFS api changes, that is the current maximum file size regardless of the file system (on x86 that is).

    A 9 million terabyte file size limit isn't a large problem for me ....

  21. Don't use sigma-delta A/D and D/A convertes. on Realtime Signal Processing for Unix? · · Score: 4, Informative

    Many A/D and D/A converters use sigma-delta converters (Look for words like: "one bit converter" or "bit stream", they are variants of this technology). Most sound cards use these sigma-delta converters, so do many A/D and D/A cards for PC, especially those with high dynamic range (many bits ...). These converters have excellent linearity, low distortion, and are inexpensive, but they have a significant time delay, so you might have more than 1 ms delay in the A/D converter alone. No real time OS can work around that.

    Be sure that you select A/D and D/A converters with "sub ms" time delay.

  22. Re:First impression on Red Hat 7.2 Released · · Score: 1

    geirt wrote:

    >The kernel is 2.4.7 + a lot of patches. Since RedHat 7.1 is at kernel 2.4.9-6 already, I believe
    >that we will see an updated kernel soon.

    Well, the new kernel is already out (as well as a new glibc):

    -rw-rw-r-- 1 19837 235 5193088 oct 22 01:17 glibc-2.2.4-19.i386.rpm
    -rw-rw-r-- 1 19837 235 8964940 oct 22 01:19 glibc-common-2.2.4-19.i386.rpm
    -rw-rw-r-- 1 19837 235 10203453 oct 22 01:19 glibc-devel-2.2.4-19.i386.rpm
    -rw-rw-r-- 1 19837 235 8903754 oct 22 01:19 glibc-profile-2.2.4-19.i386.rpm
    -rw-rw-r-- 1 2220 235 10099400 oct 22 10:33 kernel-2.4.9-7.i386.rpm
    -rw-rw-r-- 1 2220 235 4092573 oct 22 10:30 kernel-BOOT-2.4.9-7.i386.rpm
    -rw-rw-r-- 1 2220 235 1658513 oct 22 10:32 kernel-doc-2.4.9-7.i386.rpm
    -rw-rw-r-- 1 2220 235 1147039 oct 22 10:34 kernel-headers-2.4.9-7.i386.rpm
    -rw-rw-r-- 1 2220 235 24577441 oct 22 10:32 kernel-source-2.4.9-7.i386.rpm
    -rw-rw-r-- 1 19837 235 520852 oct 22 01:15 mew-1.94.2-12.i386.rpm
    -rw-rw-r-- 1 19837 235 30311 oct 22 01:20 nscd-2.2.4-19.i386.rpm
    -rw-rw-r-- 1 19837 235 172116 oct 22 01:16 openssh-2.9p2-9.i386.rpm
    -rw-rw-r-- 1 19837 235 37105 oct 22 01:16 openssh-askpass-2.9p2-9.i386.rpm
    -rw-rw-r-- 1 19837 235 19000 oct 22 01:17 openssh-askpass-gnome-2.9p2-9.i386.rpm
    -rw-rw-r-- 1 19837 235 223690 oct 22 01:16 openssh-clients-2.9p2-9.i386.rpm
    -rw-rw-r-- 1 19837 235 160517 oct 22 01:16 openssh-server-2.9p2-9.i386.rpm
    -rw-rw-r-- 1 19837 235 983005 oct 22 01:16 squid-2.4.STABLE1-6.i386.rpm
    -rw-rw-r-- 1 19837 235 938913 oct 22 01:15 util-linux-2.11f-12.i386.rpm

  23. First impression on Red Hat 7.2 Released · · Score: 5, Insightful

    I have been playing with the 7.2 betas (roswell) since it came out, and with the 7.2 release for about a week now.

    I am very pleased with Redhat 7.2, it has given me very few problems, and it was the first Linux distribution that installed into my laptop without any tweaks.

    The main enhancements (as visible by the user):

    Grub instead of lilo (but you can still use lilo if you want to ..). Grub is a great boot loader, similar to the "boot monitor" of real Unix hardware. Grub understands the file system, so you do not need to reinstall Grub every time you update your kernel (like you have to with lilo). Once you are in the grub boot promt, you can boot any OS on your system (eg. from a floppy)

    Mozilla and Nautilus: (I am a gnome user)

    Mozilla 0.9.2.1 is a rather old release, but it was the release chosen by Netscape for NS6.1 so it is quite good. Nautilus is 1.0.4 + a lot of patches from RH (Alan Cox ?) to speed things up. Natilus is still somewhat slow, but I don't use file managers so much, so I don't care. I think that you should have at least 128 MB ram to run it, is was slow on one of my test machines with 64MB ram and a sub optimal disk system. Seeing the speed and stability improvements of Mozilla in the last 6 months, I am quite confident that Nutilus will be a great file manager (++) in a short time frame. It is a very good "eye candy", and impresses every Windows user seeing it. If you for one reason or another, don't like Nautilus, use the good old GNU Midnight Commander instead (yes it is on the CD).

    Kernel, gcc, ptyhon, etc

    The kernel is 2.4.7 + a lot of patches. Since RedHat 7.1 is at kernel 2.4.9-6 already, I believe that we will see an updated kernel soon. The main compiler is RedHats own 2.96 + modifications, and python is at 1.5.2-35. You will find gcc 3.01 and python 2.1.1 on the CD which can be installed separately. RedHat 8.0 will probably use these as default.

    Postfix, Apache:

    Redhat has dropped support for Postfix (a sendmail replacement), which used to be on the Powertools CD. I really don't know why, but I hope that the next RedHat release will fix this major bug. Apache is the rock solid 1.3.20.

    Executive Summary:

    RH7.2 is a polished good distribution. Since it is a .2 version, RedHat is going to support it for a looong time, and it will become the first choice for many system administrators for serious linux servers (that is, until 8.2 is released).

  24. Look to OS/2 ... on Transgaming Bringing Windows Games to Linux(?) · · Score: 4, Insightful

    I think it is a bad idea to try to make Linux run Windows executables. IBM made this mistake with OS/2. OS/2 ran Windows applications almost as good (some say even better than) on native Windows. The result was that programmers wrote applications for Windows only, they ran after all on OS/2 also. Little native OS/2 software was written.

    Microsoft made Windows a moving target (and it still is ...), making it impossible for IBM to have the Windows emulation work in OS/2 for every respin of Windows. The rest is history, please don't let this happen once again with Linux.

  25. RedHat have the same problems on Newest Mandrake Linux Delayed · · Score: 4, Offtopic

    I believe RedHat have the same problems, since RedHat 7.2 has been ready (even on the mirrors) for some time now, but they will not distibute it (ie. add the everyone-read bit to the file permissions) until they have the CDs ready.

    The RedHat 7.2 relase is available trough rsync ....

    $ rsync -av csociety-ftp.ecn.purdue.edu::pub/redhat/redhat/lin ux/7.2/en/iso

    *** Welcome to the Purdue University Computer Society RSYNC Server
    *** Purdue University, West Lafayette, IN
    http://csociety.ecn.purdue.edu/

    This archive is available via FTP, HTTP, and RSYNC at:
    ftp://csociety-ftp.ecn.purdue.edu/pub/
    http://csociety-ftp.ecn.purdue.edu/pub/
    rsync://csociety-ftp.ecn.purdue.edu/pub/

    Report problems to ftp@csociety.ecn.purdue.edu

    receiving file list ... done
    dr-x------ 4096 2001/10/05 01:54:02 iso
    dr-x------ 4096 2001/10/04 02:01:50 iso/doc
    -rw-r--r-- 50 2001/10/04 02:02:00 iso/doc/MD5SUM
    -rw-r--r-- 624476160 2001/10/04 00:35:00 iso/doc/enigma-docs.iso
    dr-x------ 4096 2001/10/04 02:03:42 iso/i386
    -rw-r--r-- 226 2001/10/04 02:04:22 iso/i386/MD5SUM
    -rw-r--r-- 680282112 2001/10/04 00:27:19 iso/i386/enigma-SRPMS-disc1.iso
    -rw-r--r-- 542537728 2001/10/04 00:29:25 iso/i386/enigma-SRPMS-disc2.iso
    -rw-r--r-- 677961728 2001/10/04 00:22:08 iso/i386/enigma-i386-disc1.iso
    -rw-r--r-- 669429760 2001/10/04 00:24:42 iso/i386/enigma-i386-disc2.iso
    wrote 94 bytes read 691 bytes 314.00 bytes/sec
    total size is 3194687764 speedup is 4069665.94


    $ rsync -av csociety-ftp.ecn.purdue.edu::pub/redhat/redhat/lin ux/7.2/en/iso/i386/MD5SUM .

    *** Welcome to the Purdue University Computer Society RSYNC Server
    *** Purdue University, West Lafayette, IN
    http://csociety.ecn.purdue.edu/

    This archive is available via FTP, HTTP, and RSYNC at:
    ftp://csociety-ftp.ecn.purdue.edu/pub/
    http://csociety-ftp.ecn.purdue.edu/pub/
    rsync://csociety-ftp.ecn.purdue.edu/pub/

    Report problems to ftp@csociety.ecn.purdue.edu

    receiving file list ... done
    wrote 106 bytes read 500 bytes 242.40 bytes/sec
    total size is 226 speedup is 0.37


    $ cat MD5SUM
    efab549656a1a85ab8fa39eb873eff0e enigma-SRPMS-disc1.iso
    70703897af7703b40e41777a3aa186c3 enigma-SRPMS-disc2.iso
    cf7bce0c1cdbfedfae29e60aef202f6f enigma-i386-disc1.iso
    fd705b3e5d0e37a828db35d21195a9f6 enigma-i386-disc2.iso

    Note that the files are dated 2001/10/04