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Make Ajax much faster with Tomcat Non-Blocking I/O (NIO) in its Advanced IO modules

Using Non-Blocking I/O (NIO) improves server performance drastically because of its efficient use of system resources (threads). The gain in performance is very noticeable in Ajax applications. It also lets you control system-resource usage on a server under pressure. This article explains how to optimize your server for performance during the handling of both Ajax and regular requests.

Survey, purchase MS Lic then wiped it for Linux Install?

Google docs Linux - MS license Survey...!
Try my survey if you have a moment.
Note, due to alot of comments and feedback about additional items, the Survey has grown,  amazingly, hundreds of responses and 
dozens of new questions, as suggested by viewers.
Also, Put on and it's getting some attention !
See what people are saying about this...very interesting.

Linux Distros Are Like Lays Potato Chips...

... You Can't Have Just One!

Multi-booting - My Way

I've been multi-booting since I first came to Linux. Originally, it was due to my transition from MS Windows to GNU/Linux. Later, it was because I wanted to try more distributions. I was still hunting for the one that "fit" me best. I've since found that distro (Slackware). However, I still have multiple operating systems on my computer for varying reasons.


My current hard drive partition and usage map looks like this:

SATA 1 - Main/Secondary OS + Linux Archive

Primary - 25Gig: /(root) - Slackware................../dev/sda1 (ext3)

Primary - 50Gig: /home - Slackware..................../dev/sda2 (ext3)

Extended - 175Gig:..................................../dev/sda3
Partition - 25Gig: /(root) - Debian.........../dev/sda5 (ext3)
Partition - 50Gig: /home - Debian............./dev/sda6 (ext3)

Partition - 2Gig: /swap (common)............../dev/sda7 (swap)

Partition - 98Gig: Linux Archive............../dev/sda8 (ext2)

SATA 2 - MS Windows + Experimental Operating Systems

Primary - 25Gig: MS Windows Main....................../dev/sdb1 (ntfs)

Primary - 25Gig: MS Windows Programs................../dev/sdb2 (ntfs)

Extended - 200Gig:..................................../dev/sdb3
Partition - 2Gig: /swap (common)............../dev/sdb5 (swap)

Partition - 15Gig: /(root) - GNU/Linux......../dev/sdb6
Partition - 25Gig: /home - GNU/Linux........../dev/sdb7

Partition - 15Gig: /(root) - GNU/Linux......../dev/sdb8
Partition - 25Gig: /home - GNU/Linux........../dev/sdb9

Partition - 15Gig: /(root) - GNU/Linux......../dev/sdb10
Partition - 25Gig: /home - GNU/Linux........../dev/sdb11

Partition - 15Gig: /(root) - GNU/Linux......../dev/sdb12
Partition - 25Gig: /home - GNU/Linux........../dev/sdb13

Partition - 15Gig: /(root) - GNU/Linux......../dev/sdb14
Partition - 23Gig: /home - GNU/Linux........../dev/sdb15

EIDE 1 - Backups

Primary - 50Gig: Slackware Backups..................../dev/hda1 (ext2)

Primary - 50Gig: Debian Backups......................./dev/hda2 (ext2)

Extended - 150Gig:..................................../dev/hda3
Partition - 50Gig: MS Windows Backups........./dev/hda5 (FAT32)

Partition - 50Gig: Other OS Backups.........../dev/hda6 (ext2)

Partition - 50Gig: OS Common Storage........../dev/hda7 (FAT32)


 These three drives add up to three quarters of a Terabyte of space... way more than I actually need. However, space is cheap these days. I still remember paying $100 for a 10Gig drive less than ten years ago. Previously, SATA 1 and 2 were in RAID 1 (mirrored) configuration with MS Win XP Pro on them. What a waste. I rarely ever boot that OS these days (games only), so a broke the RAID down and repartitioned/reinstalled everything on my system.

The ten partitions you see on the SATA 2 drive are my experimental Linux slots. When this partition map was made, I intended to put CentOS, Arch, and Ark back on them, with the last two saved for Gentoo and maybe FreeBSD. I haven't gotten around to installing them yet, though. 

A few things to take note of when partitioning and multi-booting in this fashion:

1) Remember the SATA 15 partition limit. Many newer distros use the libATA kernel drivers which force drive recognition as SATA regardless of whether the drive is EIDE or SATA, so for this reason remember to place your /common partitions and /swap partitions on the lower numbered ones. A libATA distro installed anywhere else on the lower 15 partitions (or another drive) will still be able to "see" and mount them this way.

2) MS Windows is like the "Borg" when it comes to being installed on a computer with other operating systems. It seeks out and "destroys" other operating systems. Be sure to install MS Windows first. It needs to be on the first partition of whatever drive you're installing it on. After which, you can install your GNU/Linux distros safely.

3) Install your MBR controlling distribution last, time-wise, regardless of which partition/drive you're installing on. This will allow it, especially in the case of Debian's excellent GRUB, to "see" all the other installations and write them into your menu.lst for you. Even though Slackware is my primary operating system, and since I don't use LILO, I allow Debian to control the MBR and boot my system with its GRUB.

4) Lastly, as in the case above, if your MS Windows installation is on a different drive than your MBR controlling OS, then your BIOS may have troubles booting the correct drive. No matter what you choose in BIOS as the first device, the Windows drive will boot. The reason for this is that Windows installs a bootable flag on its own drive. This flag gets priority from the BIOS. To set a bootable flag on the drive that you want to boot will require a bit of manipulation using a Live Linux CD* and the fdisk command.

Boot your Live CD and start it. From a terminal session within the CD do the following:

 # fdisk /dev/

fdisk> a (option to toggle bootable flag on drive

--partition number? 1 (first partition on the drive)

fdisk> w (command to write the new info to disk and exit fdisk)

--bootable flag reset for this drive

This will set the bootable flag to the drive you choose. Reboot, go into BIOS setup and choose your first boot drive. It should boot fine now.

 *Another option to use is the way I actually did it on my own system... I used SLAX on a flash drive to perform the fdisk above. Worked like a champ!

Anyway, that's the way my system is set up. Whenever I add or change operating systems, I just edit the Debian /boot/grub/menu.lst to reflect those changes.

Have fun with it!

 Until next time...

V. T. Eric Layton

***Tempus Fugits***







X Failed, xserver-1.4.2 linux-2.4.x



X.Org X Server 1.4.2
Release Date: 11 June 2008
X Protocol Version 11, Revision 0
Build Operating System: Linux i686
Current Operating System: Linux tux 2.4.37-Build6 #1 SMP Tue Mar 31 09:35:35 JST 2009 i686
Build Date: 31 March 2009 11:24:47AM

(WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
(EE) Failed to load module "glx" (module does not exist, 0)
(WW) NEOMAGIC(0): Unable to estimate virtual size
(EE) xf86OpenSerial: Cannot open device /dev/input/mouce No such file or directory.
(EE) Mouse0: cannot open input device
(EE) PreInit failed for input device "Mouse0"

---- [/dev/input/*]

# ls -l /dev/input
total 0
crw-rw---- 1 root root 13, 64 Mar 30 18:45 event0
crw-rw---- 1 root root 13, 65 Mar 30 18:45 event1
crw-rw---- 1 root root 10, 150 Mar 30 18:48 keyboard
crw-rw---- 1 root root 13, 63 Mar 30 18:46 mice
crw-rw---- 1 root root 10, 149 Mar 30 18:48 mouse
crw-rw---- 1 root root 13, 32 Mar 30 18:47 mouse0



Problem with LAN MOUNTS

It seems the only major difficulty that still exists for me in swapping from WIN to LINUX is the management of PERMISSIONS!!

 For me it is a convoluted hit and miss affair ... and is continually proving a thorn in my side.

 The latest nightmare is trying to get the correct permission allocated to simply mounted network shares!! Why is it so difficult???

My WorkStation runs latest pclos 2009.1 KDE ... it contects to shares from two other machines .. one an XP 'fileserver' that holds all dynamic data files and the other is a LAMP server running under pclos 2007 GNOME ... my local LAMP host.

The XP Fileserver exposes SAMBA shares to the network ... the LAMP Server exposed NFS shares to the network.

These XP and LAMP shares are mounted on my PCLOS workstation via the Control Centre >> Network Sharing >> Configure NFS / Windows Shares

Here is the fstab file:
#Entry for /dev/hda5 :
UUID=b8ed29e5-ff38-483d-b639-102d2617b8de / ext3 defaults 1 1
none /dev/pts devpts mode=0620 0 0

#Entry for /dev/hda7 :
UUID=98656360-c225-4f8b-a7b5-3cf7d96e856b /home ext3 defaults 1 2

#Entry for /dev/hdb2 :
UUID=BC5C0CB25C0C6A0A /media/Spare_NTFS ntfs-3g defaults,locale=en_US.UTF-8 0 0

#Entry for /dev/hda1 :
UUID=7EB016B7B01675BD /media/hda1 ntfs-3g defaults,locale=en_US.UTF-8 0 0

//pc-cme/Foyer /mnt/Foyer cifs user,credentials=/etc/samba/auth.pc-cme.administrator,sync,soft 0 0
//pc-cme/JohnStuff /mnt/JohnStuff cifs user,credentials=/etc/samba/auth.pc-cme.administrator 0 0
//pc-cme/MAXBin /mnt/MAXBin cifs user,credentials=/etc/samba/auth.pc-cme.administrator,sync,soft 0 0
//pc-cme/Music /mnt/Music cifs user,credentials=/etc/samba/auth.pc-cme.administrator,sync,soft 0 0
//pc-cme/Photos /mnt/Photos cifs user,credentials=/etc/samba/auth.pc-cme.administrator,sync,soft 0 0
//pc-cme/Storage /mnt/Storage cifs user,credentials=/etc/samba/auth.pc-cme.administrator,sync,soft 0 0

lnxlamp:/var/www /mnt/www nfs user,sync,rsize=8192,wsize=8192,soft 0 0

none /proc proc defaults 0 0

#Entry for /dev/hda6 :
UUID=5a9c8cd5-f653-49ee-942d-b919c5e9cd5b swap swap defaults 0 0

The the directories under "/mnt", of course are owned by ROOT, but have been given 777 permissions by root prior to mounting.

The problem is that everytime a file is written to any of the mounted shares from my workstation [logged on as a USER, not ROOT] i get the message ...

"Could not change permissions for <filename>"

... for each file that is copied/moved to the mounted share, whether it the SAMBA or NFS share.

I think i understand the reason why .... it is because the Mount Points on my PCLOS client are owned by Root ... and while these Moutn Points have been given 777 permissions, it does not permit the permissions of the files to be altered by a user other than root, following transfer to their respective servers [Why is it trying to 'change permissions' anyway????]

I thought i would fix it by moving the mount points on my WorkStation to within the "/home/myusername" directory, and ensured that the Mount Points were Owned by me and my group!!!

Sounds logical *keh?* ...

HOWEVER, following remounting of the shares to these 'USER owned' mount points, the system forces a change of ownership of my Mount Points to that of ROOT!! ... and i find i am back in the same position as when the Mount Points where under "/mnt"!!

And, annoyingly, the problem persists!!

Any clues GURUS ... *smile*???

Thx Rfah


Searchable group discussions?

I've added few how-to in group discussions. Now I am trying to search if those posts can be searched from search option, I am amazed to see that none of the discussion contents are searchable.

I am wondering.. what is the point of adding group discussions when its not searchable?


NOOB's adventure in Linux From Scratch

 Hello again,

This morning I find myself eating a bit of crow, instead of following the link provided on the LFS prerequisites page now embedded into memory,  I typed in the address to the Linux User's Guide  and went immediately to a General Disclaimer page... this is not the case when you follow the link in the LFS site.. they send you to  missing the Disclaimer page all together.

  So, it seems that the errors I was complaining about are already in the process of being repaired. 

  I've sent an email to the webmaster of the site,  apologizing for my mistake and informing him of how sites are linking directly to the guide and his pop up windows being skipped over.

  Just goes to show how the community works quickly to fix mistakes .. Bravo!!


Linux on Netbooks

It is so annoying (but not unexpected) that Microsoft swooped in and fixed it so you can't find a netbook with Linux on it in any store, but this is the icing on the cake:

I was in Costco a couple of weeks ago and I was looking over the netbooks to see if there was one with Linux installed (of course there wasn't).  The salesman came up and asked if I had any questions.  I said "yes, where can I get a one of these with a decent operating system instead of Windows".

I can say that I won't ever buy another machine with Windoze pre-installed. I did that once and I have regretted it ever since. I tried to get my money back for the unused copy of Windoze that came with it, but finally gave up. I am mad at myself for giving up too easily, I should have fought the battle just on principle.

It occurred to me that we should grab the "" URL and put up a rebuttal, but it looks like somebody already has it. I certainly hope it isn't a Redmond lackey cybersquatting.

NOOB's adventures in Linux From Scratch

Back again,

 I'm about 3/4 of the way thru the first prerequisite . Feeling the first inkling of understanding of what it takes to put a command line together. Not just a  single command. 

   I personally don't think that the  could be the best one to learn from as it's somewhat dated and I the NOOB even find many mistakes ...  It for one is not easy to follow,  it jumps all over the place. Command examples  are not with the paragraph that  writes about it. They're  is sometimes three or four paragraphs away from it, with no direction or no# linking the example with the paragraph... confusing to say the least.  There are mis-spelled commands.  Easy for an established person to realize there's a problem here. But, I found myself lost on many occasions following along blindly lost as to why I wasn't getting the same answer at they get.. or getting an error about the command , only IRC and Google saved me.  None the less,  I'm committed to my goal of getting the knowledge I need to successfully build LFS. I'll finish reading and making notes, and follow up with google and other pages as needed. Actually, thats probably the reason I'll be more competent. I won't give up... I'm making everything work before I move on so the end result is more information is sticking to my brain because of the mistakes :) It is aggravating but that's exactly why I'm retaining more info ???

  I've been at this now about 3 weeks. I quickly read through the prerequisites only to fall flat on my face building LFS. I've really made the point of studying all the info pointed out in the prerequisites  this that I will fully comprehend what I've read.  At this point in time , I believe that just the prerequisites will not be enough for me. We shall soon see.



Intel Core 2 Quad... Which version of Linux do I have to install?

This is my first contribution to the community, I hope it will be at least from a practical point of view, useful for some of the new Linux users, as I actually am.

I recently purchased a nice computer. I mounted the components (which was kind of an adventure) and decided to install Debian on it. I faced the very first question as I was going to download it: which architecture is the one I should use?

My processor is an Intel Core 2 Quad 8200, so I knew I could run on 64-bits.  But the amd64 version looked weird to me, since my computer had an Intel processor (Intel64...) not an AMD. The answer is quite straight forward: for Core 2 amd64 is the one.

Read more... Comment (0)

How I got involved with Linux

I am a technical writer. I've written hundreds of thousands of words about the Linux operating system over the years. I currently write for three different companies - one of them our beloved

I thought I would introduce myself by way of discussing how I got involved with Linux in the beginning....

I came into computers rather late in life. I was just joining the professional world as a professor at a university and realized I had to have my first computer. So I bought an Acer Aspire with a 75 Mhz CPU. At the time it was sweet. I was on AOL and having a blast...that is until Windows 95 decided to do its thing and reveal to me my first "BOSD". At that point I assumed it was a "feature" and plodded on. But that "feature" continued creeping into my daily computing life. No matter what I was doing I found myself having to reboot my machine with either the three or the one finger salute. 

After a few years of that I heard the whispers of another operating system - one that wouldn't frustrate me beyond belief, one that would actually do what I wanted it to do. Being the curious monkey I am I had to know what this operating system was. That was circa 1998 and I finally heard the name Linux.

Being on dial up, the only way I was going to have this operating system was either: 1) from Cheapbytes or 2) from the local retail. I got lucky and the local retail shop had a copy of Caldera OpenLinux. Believe it or not I did get this installed. It was thermo-nuclear physics rough. I had never installed an operating system before and was, well, a bit taken aback by the process. 

Eventually it was installed and I was up and running. Only problem was I wasn't doing much. It took me a while to finally figure out I was the proud owner of a winmodem, so I couldn't get on line.

Ah the beauty of the US Robtics external dial up modem. It worked like a charm and I had Linux up and running and on line! I flipped the bird to Windows and never looked back.

Now I can say I have tried every distribution I can get my hands on. I have covered nearly every aspect of Linux one one or more sites. My writing about Linux has been published and translated into multiple languages.

Linux has been, and always shall be, my friend.

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