Partition, Volume, Disk, Drive what is the difference?

   

Western Digital Raptor X 150 GByte 10,000 rpm.
Western Digital Raptor X 150 GByte 10,000 rpm. A unique hard disk with transparent cover. It was produced in 2006 and was expensive. Really expensive and didn’t appeal to many. It was the trent of transparent PC cases which promote the soecial design of mitherboards, Disks and graffic cards.
 In Windows operating system a user only sees disks when he clicks the computer icon. 

Are they real physical disks? How a disk is configured in Windows?

The story is long and starts from the early home computers. I don’t write personal computers because this is a trademark from IBM, also known as PC. 

_Drive is the machine that reads and writes the storage medium. The medium can be a cassette, a floppy disk, a hard disk, CD, flash memory etc. To be more clear the cassette is medium of data but alone can’t be accessed. It needs a cassette drive. The same with the CD or Floppy Disk. Of course floppy disks drives are obsolete today. However cassette drives still reign in the enterprise computer sector.  

HP digital cassete drive.
HP digital cassete drive. The cassette drives are not dead yet. They offer immense storage at very low price. The only disavantage is that files are not seeked fast.
 The professional cassette drives are very expensive, but the data cassettes still offer immense and the most affordable data storage today. The common HDD and SSD are acronyms for Hard Disk Drive and Solid State Drive. In the case of a HDD the data medium is the hard disk enclosed by a meta box with a motor and heads which read and write data to the disk. In the case of SSD the medium is chips with transistors on an electronic board. Driver and drive are not the same. Drive is hardware, driver is the software which helps the operating system to control the Drive. Usually the operating system includes the proper drivers but some times extra software is needed for an new drive which is named driver. For deep control and informations about the physical drives in windows type DISKPART . DISKPART shows more details and has more commands than the Disk Management. To view the physical drives use the command LIST DISK . The drives are named as DISK 0 for the first, DISK 1 for the second ,DISK 2 for the third etc. What we see at clicking the computer icon of windows is not necessarily physicall drives but partitions or volumes too. For selecting the drive you want to use  type SELECT DISK 0 for the first physical drive or SELECT DISK 1 for the second etc. The command CLEAN erases everything from the selecting disk.

_Partition as the name suggests is a partition of the disk. It is used mainly on HDDs and SSDs. There are many reasons to partition a disk. The first is the economical. Nowadays the rotational hard disks are very cheap and I avoid partitioning. However 15 years ago it was a tool to make a single hard disk very usefull. You can install different Operating Systems on a single hard disk. For example in a single disk I created four partitions. On the first I installed the legendary Windows 98SE, on the second the revolutionary Windows NT 4.0 and on the last two partitions the simple and beautiful Corel Linux. 

Windows NT 4.0 was a game changer.
Windows NT 4.0 was a game changer. Away from the classic DOS provided flexibility and security to disks. It wasn’t very user friendly like windows 98 and lacked harware compability. Actually the very succefull Windows XP is a hybrid of Windows 98 and Windows NT 4.0.
  At the start the first selection of the boot loader was between Linux and Windows and if I selected Windows, the next selection was between Windows 98 or Windows NT 4.0 . For achieving that I had to partition the hard disk into four partitions with different sizes. Linux needs two partitions. Usually the biggest partition was dedicated to Windows 98. 

The  increasing rate of the hard disk capacity is not the same like in Ram or CPUs and it usually surpass the expectations of programmers. My first disk in 1997 was an enormous 6 GByte Quantum and costed 100,000 drachmas around 300 dollars. After 18 years a 6 TByte (6,000 GByte) disk costs the same for one thousand times bigger capacity. In 1997 the windows 95 I had, was recognizing only FAT12 and FAT16 formatting systems. FAT16 however had a limit of two GByte partitions. So I had unwillingly steparated the hard disk into three partitions. After two years in 1999 I installed three operating systems on a single disk and I wanted each operating system to access the files created by the other two operating systems. Windows 98 could recognize only FAT32 and FAT16, Windows NT 4.0 only NTFS and FAT16 and Linux only EXT2 and FAT16. So the common formatting system was FAT16 which restricted the partitions to 2 GByte. Next in 2003 I wanted to have both windows XP and Mandriva Linux which was the successor of my beloved Red Hat linux. Windows XP could recognize FAT32 and NTFS formatting systems and Linux Mandriva EXT2 and FAT32. This time the common formatting system was FAT32. However FAT32 has restrictions. Under Windows XP the biggest partition with FAT32, I could format was 32 GBytes. Also FAT32 doesn’t permit files over 4 GByte. Again I had  created unwillingly many 32 GByte partitions. Nowadays hard disks are very cheap but most laptops don’t have more than one disk. You can’t  install an operating system like windows on a usb hard drive. If you want to have multiple operating systems on a laptop the partitioning is the only way. OS X  and its boot camp is a nice case of multiple operating system on a single disk.

The main kind of partition is the active. The active partition is the partitions which is bootable and usually holds the operating system. Only one partition can be made active. In the case of multiple operating systems on a disk, a boot loader program on the active partition redirects to the selected operating system on different partitions. A hard disk which it isn’t bootable doesn’t need an active partition. Usually the usb hard disks don’t have active partitions.

Under windows FAT32 a disk is restrict to one primary partition and one extended partition. Only the primary partition can be active and only that can have the main files of the operating system. Of course the primary partition can be inactive without operating system.  The extended partition is always subdivided into one or multiple logical partitions. That was a relic of the DOS and windows95,98,Me era. After the windows NT 4.0 and Windows XP and the advent of NTFS formatting system the rules are relaxed and the primary partitions can be as many as four. For a detail view o Partition type DISKPART command and afterwards LIST PARTITION.

The informations about how a disk is partitioned are stored in area which is the old MBR (Master Book Record) or the new GPT (GUID Partition table). In the MBR the informations are stored in one place and if that place is corrupted the data on the disk is unreachable. The GPT store the informations in multiple places and is more robust. The MBR is old and has limitations. Only four primary partitions are permitted and more crucially the biggest drives it can support is 2TByte. That was a big obstacle to the expansion of bigger than 2TByte disks. The GPT is not supported by all 32bit versions of Windows including windows XP,vista,7,8. The 4 GByte limit of memory in a 32bit OS is not such a problem as the 2 TByte hard disk limit. Windows XP 32bit, 64 bit and earlier versions of Windows can’t be installed on GPT disks. The MBR dates back to 1983 and it’s time to be changed.   

A disk under windows can be configured as Basic or Dynamic. A Basic disk support all the properties written before. A dynamic offers RAID capabilities inside Windows without RAID hardware. It is not offered in all versions of windows. It is a premium feature and only professional and above editions provide the RAID functionality of Dynamic discs. The windows don’t use directly the RAID name due to copyright issues. Instead windows uses the spanned, striped and mirrored disk which are equivalent to RAID configurations.

Finally what is Volume? The computer icon on windows shows disks with their assigned letter. That letter distinguishes the Volumes of an operating system. So a volume can be a primary partition, a logical partition, a whole disk, or a combination of dynamic disks (mirror disks, stripped disks or spanned disks). Volume is what the user see and doesn’t have to care what lies behind it. To view the volumes type the command DISKPART and afterwards LIST VOLUMES.

Sources:  

http://web.archive.org/web/20150514233235/http://www.howtogeek.com/193669/whats-the-difference-between-gpt-and-mbr-when-partitioning-a-drive/

http://web.archive.org/web/20150515091643/https://support.microsoft.com/en-us/kb/300415

Hard disk redundancy in Windows and OSX.

The last 18 years I’m a computer user, I faced three times a great loss of data from corrupted disks. In computing there are two kinds of people, those who lost files and those who will loose files. Every hard disk will eventually temporary or permantly fail after three to ten years.

The obvious and easy answer to this problem is making a back up. That process is good but its boring and time consuming. A proper backup should be done continously and incrementally. 

 

Time machine of OS X is a back up app,  by far better from the windows back up.
Time machine of OS X is a back up app, by far better from the windows back up.
 The time machine application of OS X is a nice solution. Back Up has two disadvantages. First the automatic interval of incremental Back Up can take a day. Second, a complete restore of a failed hard disk can take five hours or even more. 

The best solution is RAID 1 (Redundant Array of Inexpensive Disks). As its acronym indicates, it is an inexpensive solution of data safety. The same data is  written and read in at least two disks at the same time. The probability of both disk failing simultaneously is extremly rare. There are many kinds of RAID types. Initially RAID was based on hardware. A RAID card or an embedded raid controller on the motherboard was needed. Hardware RAID offers speed and reliability. Nevertheless modern operating systems and fast CPUs can emulated RAID without any use of special hardware. 

Windows 7 professional and OS X Lion 10.7 offer software RAID 1 with some limitations. Of course the hardware RAID is the best but software RAID is equally safe.

Windows 7 professional doesn’t use the name RAID 1 for copyright reasons. Instead it uses the mirrored disks name. Mirrored disks can’t be created through USB. From my experiences SATA disks directly connected to the motherboard work fine as mirrored disks. In desktops its easy to add two extra disks and make them mirrored. 

On laptops the case is different. Most laptops have one bay for hard disk and one for the DVD drive.  

Many big laptops have double HDD bays. These are ideal for Raid 1 mirrored disks.
Many big laptops have double HDD bays. These are ideal for Raid 1 mirrored disks.
 Some bigger ones 17″ and 18″ have two bays for HDD. Again this doesn’t help to create mirrored disks. The drive in which the windows 7 professional  operating system  is installed can’t be mirrored afterwards. Althought Windows 7 professional  can be clean installed from the beginning on a ready made two mirrored disks. 

For laptops a DVD caddy bay can help. 

  Removing the DVD drive we replaced it with a caddy DVD drive that accepts a hard disk. That way a typical laptop can at least have two hard disks or even three. 

The way of creating mirror disks is simple under windows 7 professional or Ultimate. (Not all windows 7 versions offered mirrored disks. Windows 7 starter, basic or premium don’t offer that potential).   

Disk Management of Windows 7.
Disk Management of Windows 7.
 Right click the computer icon and select Computer Management. You must have logged in as administrator. then select disk management. Now the first step is to make the hard disks we want to mirror, as dynamic. Second step is to right click and select mirror disk from one of the two disks and from the next window insert the other disk to be mirrored.  

Mirrored disks RAID 1 under windows 7 professional.
Mirrored disks RAID 1 under windows 7 professional.
 That’s all. A new hard disk will appear on My Computer which is actually a bunch of two disks. In case one of the two disk failed the windows will try to fix the problem and notice the user. Otherwise a classical backup will be needed and a replacement disk to be mirrored. One way or another the data won’t be lost. 

On OS X the disk utility app permit the Raid 1 with usb disks.  

 This is very convenient and safe way to expand your data storage. Also theoretically you can clean install an OS X opeeating system on RAID 1 disks. The way of creating a RAID volume on OSX is far easier than in Windows 7 Professional. 

Macbook retina 2015, does it worth buying it.

I entered the computer world in 1997. I wasn’t a DOS user neither windows 3.11 user and I regret for losing that era. I started from the golden age of Internet and CDs. Of course my first computer was a windows primitive desktop. It was an ugly beige box with a 150MHz pentium and 16 MBytes memory and 1Mbyte graffic card. Only the respectable Sony display was decent enough.

In 1997 Steve Jobs had just returned in Apple. Also the arogant Rainbow importer of apple computers was the worst computer company I have ever met. So an apple computer wasn’t a choice. In 2004 I bought an eMac with PowetPC processor. It was a great computer but I couldn’t find good video encoding software which was my basic interest that time. Additionally hardware wasn’t compatible with mac like nowadays. I wasn’t  impressed due to the lack of specialized software. That wasn’t the case with my second apple intel computer. The MacBook Air 2011. It was a game changer for me. A goodbye to the dark age of windows.

I’m a four year avid user of OSX. I feel like a MACaddict. This is my review about the new apple macbook retina 2015. For someone new to apple computers, it is not a bad choice. Its design is amazing and definitely the future of ultraportables.

I will start from the negatives. First of all the price. When you buy apple, you buy innovation. You buy what the others will make affordable after two years. You either wait and have old affordable technology or you choose apple. This may sound dogmatic but is true. Aple differs because it combines software with hardware seemlessly . 2.000 euros for a notebook is much. Apple since the first iMac, after has a hight price tag. It is true that the recent years the price of macbook has lowered. But on which MacBooks? The old technology MacBooks. The new retina macbooks are still expensive.

 

Macbook retina 2015, simply shows the path of future laptops.
Macbook retina 2015, simply shows the path of future laptops.

As usual the apple computers can be customized. The same is true with macbook retina. The best configuration with 512 Gbyte SSD and 1.3 GHz intel core M raise the price to 1.950 euros. The basic configuration 254 GByte SSD, 1.1 GHz intel M core is at 1.450 euros. Still I’m not impressed. The www.cpubenchmark.net for the best optional cpu for macbook retina ,the Intel Core M-5Y71 gives a mark at 2.919. Now the best optional processor for the MacBook Air mid 2011 is the 1.8 GHz (i7-2677M) dual-core Intel Core i7 with 4 MB shared L3 cache.  

 The www.cpubenchmark.net for the i7-2677M gives a mark at 2.882.

So both laptops with four years difference have the some performance. Why then I should change my MacBook Air mid2011 with the macbook retina 2015? 

In four years Intel has succeeded to lower the power consuption from 17 watt to 4.5 watt with the same performance. It is a technological leap.

That creates three big differences. The aesthetic, the weight and the noise. The lack of airfan permits a slimmer design. The lack of big copper cooler reduce the weight. No airfan and no rotational HDD bring no noise at all.

Power Mac G4 Cube 2001
Power Mac G4 Cube was the last fanless computer before macbook retina 2015. It was a powerfull computer not like the anemic macbook 2015. It was fanless but not noiceless the HDD created noise. In 2001 a SSD was just a science fiction dream.

 Even the last fanless computer of Apple, the ill fated Power Mac G4 Cube was fanless but not noiseless due to the HDD. A noiseless computer was an early dream of Steve Jobs. First attempts were a failure and the dream remained a dream during his lifetime.

Macbook retina 2015 is very slim. It is so slim that actually no conventional data port can fit. Only the earphone jack and a new type of USB, the slim USB-C

USB-C
USB-C has a similar size to micro usb but it differs in many things. It is twice as fast as USB 3.0 , it outputs 100 watt and it can be inserted by either side like the lighting connector.

A micro USB is slim enough to be fitted but if you want to avoid an extra  power port, the micro usb is underpowered. I dislike USB-C even if it is a necessary evil. I also desliked the early preference of apple to thunderbolt than USB 3.0 . Apple has a long history of proprietary or less popular data connectors like SCSI, FireWire, display port and the recent thunderbolt. That confuses consumers. The inevitable USB-C adapters raise the cost further and add weight and bulk. 

The retina display sounds impressive with its tremendous resolution. The reality is that in most cases it doesn’t help. The osx select the retina resolution when the app is written for retina display. Otherwise a non retina display compatible program will show very small icons and letters. The OSX tries to magnify applications or downscale the resolution. The result is both inferior from a conventional no retina display. For multimedia applications retina display is second to none. For office applications is not really essential. As the time passes nearly all mac software will be retina compatible.

What I like in macbook retina is its slim design and its lightness which is comparable to the first generation of iPads. It is fully aluminium even at the place between the display and the main body which in MacBook Air is a black plastic strip. 

 

With the forthcoming of macbook retina the macbook air looks very old,
With the forthcoming of macbook retina the macbook air looks very old,

I strongly believe that it will replace MacBook Air as the forthcoming low powered processors will be faster. 

The first generation of MacBook Air 2008 was critisized for being too slow. After 2011 Macbook Air’s optional faster processors were equal to the base models of MacBook Pro 13″. The market of x86 CPUs is stagnated lately. Only the ARM processors in mobile phones and tablets has a marvelous progress. The extra low powered CPUs is the next bet from Intel. Intel after 2008 produced the low powered Atom CPUs but they failed due to their very inferior perfomance. Netbooks are gradually replaced by affordable ultraportables. 

The keyboard and trackpad is what you expect from such a small and slim computer. It takes time to be accustomed. Small computers are not ideal for fast blind typing. Only the expensive models of Lenovo thinkpad offer really good keyboards. The trackpads of apple and all the trackpads in general can’t be compared to a mouse. Since macbook retina hasn’t got a proper USB port only a compatible bluetooth mouse can be used without the mess of adapters. 

In comparison with MacBook Air the macbook retina is not upgradetable or reparable at all.

The macbook air can be upgraded with a new and bigger SSD.
The macbook air can be upgraded with a new and bigger SSD.

 For example in the case of MacBook Air, battery and SSD are replaceable, the same with fan even if MacBook retina doesn’t have one. In Macbook air anything is glued and soldered . The iFixit site which I appreciate a lot, gives 1 in 10 score, the lowest in repair ability. iPhone has 6 in 10 and you can’t say that it isn’t compact.