Partitioned Disks Are Slower?

JimmyMcNulty

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http://en.wikipedia.org/wiki/Disk_partitioning

With Microsoft Windows, the standard partitioning scheme is to create a single active primary partition, the C: drive, where the operating system, user data, applications, and page file all reside. Some users, however, prefer to create multiple partitions so that the operating system can be stored separately from other kinds of data. While this scheme generally results in slightly lower performance due to additional work needing to be done by both the hard drive and the operating system[citation needed], proponents of multiple partitions generally point to the benefit of being able to erase a single partition (typically the operating system itself) while retaining the other data

8O

Is this true?
 

laitainion

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If it is I would presume that it would be because you've got less continuous data, as HDDs work best reading long streams of data in a continuous track. If you think about it, because of the different partitions you've got a 'forced' gap between data, resulting in more of your data being nearer the middle of the disc (and thus slower to read). While the logic works, I don't have any data to back this up though.
Either way, I don't think it's really worth worrying about as different partitions also means you can keep them well defragmented. As in the example, the OS can be defragged to death and then left, with all your writes being done on other drives.
 

firemist

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There are many thinks that impact the performance of a disk including the organization and amount of data on the disk. Different locations on the disk platter have different seek times. The further the head needs to move to get to the data the longer the seek time is. This is then compounded by data fragmentation that requires the head to reposition frequently to read a disk file. When a 160 G disk is partitioned into two 80 G pieces and both are accessed frequently (one for programs, one for data) there will be an increase in seek time for the head to get to the second partition as compared to having the data physically closer to the programs on the first partition. That being said, the same thing can occur if the disk has a single partition, has a lot of data, and the program file and data file are on opposite ends of the disk.

My experience is a highly fragmented single partition disk is slower than a defraged multi-partitioned disk. And a defraged single partition disk is faster than a defraged multi-partitioned disk.

Bottom line is the faster disk will be the one with fewer head movements.
 
Yes, it is true. It's a questions of resources. The thing to remember with one hard drives and multiple partitions is that all the data, no matter how many partitions or drives windows shows, is still physically contained on one drive and set of platters.

Simplistically; if you partition a drive, typically one is for the OS and one to store files and data. If you open an application, the drive needs to spin to access the program files. If you then open data or files stored on the other partition, the same physical drive needs to spin to access the program files and the stored data. Then to add to that, if your system needs to access the pagefile, it is again accessing another sector of the same physical hard drive. So, if are using a program that constantly needs to access it's program files, and you are consistently saving any changes or progress to your data, and you are using large files with the system caching the pagefile, you have three "sources" calling for data from three different locations/sectors on the same physical hard drive. The hard drive itself must then spin and the heads must move to access data as each application calls for it in order to supply each source with what it needs.

In contrast, if you have two or more drives, one hard drive for the OS, and one for stored data/files; as each source calls for data the hard drives can supply a flow of data indepedently of each other and applications or the OS does not have to "wait in line" to receive data from the hard drive.

I hope that makes sense. Good luck!
 

pat

Expert
http://en.wikipedia.org/wiki/Disk_partitioning

With Microsoft Windows, the standard partitioning scheme is to create a single active primary partition, the C: drive, where the operating system, user data, applications, and page file all reside. Some users, however, prefer to create multiple partitions so that the operating system can be stored separately from other kinds of data. While this scheme generally results in slightly lower performance due to additional work needing to be done by both the hard drive and the operating system[citation needed], proponents of multiple partitions generally point to the benefit of being able to erase a single partition (typically the operating system itself) while retaining the other data

8O

Is this true?

that's the word that means everything... Doing a separate partition for windows and data saved me much more time when reinstalling than what having a single partition would have save to me in 100 years when compared.. so, I don't care.
 

SomeJoe7777

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... you have three "sources" calling for data from three different locations/sectors on the same physical hard drive. The hard drive itself must then spin and the heads must move to access data as each application calls for it in order to supply each source with what it needs.

In contrast, if you have two or more drives, one hard drive for the OS, and one for stored data/files; as each source calls for data the hard drives can supply a flow of data indepedently of each other and applications or the OS does not have to "wait in line" to receive data from the hard drive.

That's not the question we're trying to answer here.

The issue is not 1 drive vs. 2 drives. We all know that multiple drives would translate into better performance for multiple applications requesting data from the storage subsystem simultaneously.

The issue is 1 partition vs. multiple partitions on the same physical drive.

In and of itself multiple partitions do not result in lower performance. There is no overhead in the computer where having to find data on a different partition inherently takes more time than finding the data on one partition.

However, you can impact yourself by not putting data on the partitions intelligently. For instance, if you set up a partition at the end of the disk (say we assign it the Z: drive) and put the pagefile on it, you've definitely set yourself up for a performance impact. The pagefile is now on a portion of the disk that reads and writes much slower than the outside portions of the platters, which impacts performance. Also, if you now have the above scenario where simultaneous application reads need to come from C: which is the first partition on the outside of the platters, and pagefile reads need to come from Z: on the inside of the platters, the resultant seeks between the two are now much longer and impact performance as well.

But in the same spirit, if I take a 250GB drive, partition 30GB for a C: and 8 GB for a pagefile before I do anything else, I now have everything on the outer edge of the platters, and I've prevented pagefile fragmentation as well by having it on it's own partition. In this instance, I could conceivably gain performance over Window's random placement of a pagefile on a big 250GB C: partition.
 

zenmaster

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Personally, I find no basis for the arguement that is slows NTFS performance.

One partition will clearly be faster than another partition since one will be working with the outer portion of the HDD and the other the INNER portion.

I can also see smaller FAT Tables (Or whatever you would like to call them since each File System has a slightly different name but something that maintains this type of info) may help for some file systems. I know that some systems really dont care how large this gets within reason.

There is a reason why Wikipedia is not an authorative source and why somebody marked that entry as "citation needed".