This was an interesting article ported by Kotaku on game immersion.  He has some really good points and it is a good read.

Why Don't I Lose MySelf In Games Anymore?

In my many year using Linux and other computer operating system kernels, I find Linux's memory management the best.  Only a few Linux distributions did I find memory management poor.  This was most likely due to either the kernel used, or daemons used.

Applications seem to launch quick under Linux, and the overall memory usage seems lower than other operating system kernels.  The way the Linux kernel caches application code, is done really well.  I seem to have constant issues with memory under Mac or Windows.  Issues of which do not appear under Linux.

I was surprised to see how slow Applications launch under Mac OS X 10.6.  After reading many forums, it appears to be related directly to Snow Leopard...  However, I am sure if that was the case, Apple would have resolved the issue by Mac OS X 10.6.6.

This is one of the many reasons why I keep retreating back to my Debian Linux desktop from other operating systems.  After using OS X for a few weeks, I was quickly trying to find out how to run many of my favorite open source applications on OS X.  Mainly because OS X has really awful memory management compared to Linux.  For example, I open Firefox on OS X, it can take about 20 seconds on a Dual core 2.66Mhz.  After I quit the application and open it at a later time, it again takes about 15-20 seconds to open.  However, under Linux, I open it the first time, it may take about 10 seconds.  After closing the application and re-opening it later, it takes only 2-5 seconds to open again.  This is due to the better application code caching Linux has.

An interesting example on how Linux caching works is when one uses the free command under Linux.  When I first began to use Linux, I thought it was horrible at memory management due to how much memory was in use, even after closing applications.  Actually, at the time, I thought applications were leaking memory.  However, this was not the case.  The excessive use of memory was in reality the usage of the cache.

Under Linux, when you close the application, it technically still remains in memory, but the memory is free for other uses.  If the user launches the application again, it checks the memory cache, and if it's already there, it uses that in preference.  All operating systems have this application code cache, however under Linux it does not delete the application cache unless it really needs to.  If I close Firefox now and have plenty of memory free, it will remain in the memory cache for quite awhile.  I can open new applications, and if I need Firefox again, I can open it within seconds.

I figure other operating systems have a timed application code cache, whereas it removed the cached application after a specific amount of time.  Linux only does this, if another application is requesting more memory.

I recall using NBD awhile ago for a Linux software RAID I was using with ZFS, and it had wonderfully speedy results.  Not until now do I realize how super fast NBD really is compared to Network File System or Server Message Block protocols.

The benchmarks are as follows while copying a 105MB file.

NBD	1.5 seconds
SMB	10.7 seconds
NFS	15.6 seconds

The NBD was also encrypted and being decrypted on the client machine.

It appears that Linux uses normal disk caching on the client machine when working with remote block devices.  This speeds up transfers of previously used remote data.  The initial data transfer is still below 5 seconds, making NBD quicker than the alternatives.

I now have Debian Squeeze booting on my MacBook perfectly fine.  I was rather easy, thanks to rEFIt.  You only need rEFIt to sync the GPT with the MBR, afterwards you no longer really need it.

Mostly everything worked right away, needed to manually compile and install the wireless drivers, but I'm quite used to it and it didn't take long.  Video acceleration and OpenGL work wonderfully right out of the box, thanks to the Intel chipset.

The only hardware issue I have with the MacBook is the limited amount of USB ports.  Apple expects users to use Bluetooth HID devices(Keyboard and Mouse).  I do not have a Bluetooth keyboard or mouse.  Since there is a limit of 2 USB ports, I needed to find a nice solution to make it easy to access my external storage devices without loosing the ability to use my keyboard and mouse.  The powered USB hub I bought has a very short power cord and needs to be powered or it will cause problems.

I configured my SheevaPlug with the USB hub and a wireless USB Wifi dongle to share my storage devices over the network.  This works perfectly since all my devices can access it easily now.  Also since OS X does not play nice with LUKs encrypted block devices, OS X can now also access these devices from the SheevaPlug.

The SheevaPlug is a standard ARM Cortex A8 embedded device with Debian Lenny installed on it.  Actually, it shipped with Ubuntu server, but I put Debian Lenny on there as I prefer it over Ubuntu.  The SheevaPlug has one USB port, one Ethernet port, and one SD card slot.

I found it much easier and more secure to share my externally USB device over the network using NBD.  NBD has faster transfer rates than most network file systems, as it accesses the blocks on the disk directly.  Since it accesses the blocks directly, I can export the encrypted block device over the network and let my MacBook decrypt it and store the encryption key.  Although this setup is not compatible with OS X, although it might be now.  I plan on using an exported NFS share for sharing data with Mac OS X from the encrypted storage unit.

Here is a video of my MacBook booting OS X and Debian:

I find it strange that a monolithic kernel which Linux possesses is so much more quicker and responsive than a mach BSD kernel which Mac OS X uses.  I find myself using Iceweasel via VirtualBox to browse the Internet more than using even a native OS X version of Firefox.  What's wrong with this picture?  How can a browser using through a Virtual Machine be more responsive than the same browser running on the native Operating System?  This makes very little sense to me.

To make things more interesting, here is how I have it set-up.  I am using Oracles VirtualBox on a VT-enabled Intel processor.  Inside VirtualBox, I have Debian Squeeze running with all updates and Iceweasel.  I am not running Iceweasel using Debian Squeeze's X.org server, but am using Mac OS X's X11.app X server.  Firstly, don't go and say that it's still Apple's X11.app which is making the apps more responsive than a native Aqua app, as Iceweasel and many other Linux apps are still more responsive when running on a physical computer(one which is considerably slower than the MacBook).

By responsive I mean by the application startup time and the feedback from the application.  I attempted to write in my blog on the native Mac OS X firefox browser, but my text cursor constantly skips as I typed, it was not smooth at all.  Then on Iceweasel running on Debian through VirtualBox on the same MacBook, I am able to type and the page can actually keep up with my quick typing with no lag whatsoever.  How is this possible?  I would imagine that the native application would respond more swiftly, but it does not.

I can see more of why Linux is chosen for the server environment over OS X or even Windows.  BSD is used somewhat, but if this responsive behavior is really related to a BSD kernel, then I can see why Linux is favored over BSD.

If Apple can make the iPhone more responsive than the Android, then how come Apple cannot make OS X more responsive than Linux, the core of which Android is based?  Perhaps is more to do with the extra Dalvik Java Virtual Machine which makes the Android as sluggish at times as it is.

Ironically, I use both a MacBook and an Android phone at the moment.  I plan on moving my phone platform back to Symbian OS very soon.  If Apple can fix these responsiveness issues and start-up times with their OS, then I may consider a future computer being another MacBook.  Until then, my next notebook will definitely be a Linux-based one.

Overall, Mac OS X is very nice to work with, but I still miss the responsiveness of my Linux laptop, although it was much more slower and only single cored, it oddly ran faster than OS X.  A great feature of OS X for me is going to be Bootcamp, as I can easily install an Intel-based Linux distro if I so need to.  At the moment running Linux via VirtualBox seems to work perfectly, all I need is a RAM upgrade and I'll be all set.

I guess once you try Linux(not Ubuntu) and see how wonderful the system is, it's really difficult to buy into the competitions bullshit.  Although, all of this is from a techies point of view.  I am a huge power user and tend to no upgrade until I brought the computer to it's knees.  For the most part, my last laptop was working perfectly for me.  Although the video card was the only piece which I wanted to upgrade.  The only way to upgrade a laptops video card is to buy an entirely new laptop.  Although there are some newer laptops out there now that support upgrading the video card, mine wasn't one of those.

I will forever remain a LinuxAddict.

No update for a few days is a good thing right?  Well sort of, I have been going through my UNIX knowledge and attempting to use it in Mac OS X.  Bad idea...  Mac OS X has a UNIX root, but much of the good stuff has unfortunately been removed by Apple.  No built-in package manage for managing Open Source packages.  I ended up using MacPorts again today to compile many free AV tools, such as libdvdcss and transcode.  I got a better version of Mplayer from compiling this way, rather than using the Mplayer OS X 2.  I couldn't believe how limited QuickTime is, compared to the mplayer port from MacPorts.  QuickTime is missing many codecs, such as FLV and MPeg2.

My migration from Debian to Mac OS X is turning out rather well.  During the first day, I attempted to use MacPorts to access my previous Debian applications on Mac.  This was not the best idea, it takes a very long time to compile.  It took well over 12 hours just to compile Amarok and all it's dependencies.

What do most RPG engines have in common?  A tag system!  A tag a simple bit based variable, it can either be on, or it can be off.  In many RPG engines and games, it is the driving force of the epic story lines.  Did the player do this yet, has he purchased that item, talked to that NPC, etc...