froilanr
February 26th, 2004, 09:11 AM
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Originally posted by froilanr
Off-topic!
SCSI Hardisk w/ 10,000 RPM is faster than a SCSI w/ 7, 200 RPM.
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Posted by RiderDriver:
Not necessarily true. RPM tell you have fast the disk is spinning, not the ACCESS time to get the DATA.
sorry, just had to say something about that.
__________________
RiderDriver,
I dont agree! RPM specifications of a hardisk helps to read and write data faster. So the bigger the RPM the better, but it's not
necessary in some applications.
I think you are saying the Hardisk specification SEEK TIME. The smaller the SEEK TIME (in ms), the faster it can access data.
Here's the proof why RPM specification is important!
Also some important informations when choosing or buying hardisk.:)
SOURCES:
1)
http://computer.howstuffworks.com/framed.htm?parent=hard-disk.htm&url=http://www.pcworld.com/reviews/bguide/0,guid,20,page,1,00.asp
A) Rotational speed
5400 rpm
5400 rpm to 7200 rpm
Somewhat important. Faster rotational speed means the drive reads and writes data faster. Rpm is more important if you use a PC for video or multimedia applications: Differences in rpm don't make a noticeable difference for tasks such as word processing or Web surfing. The largest drives often have the slower (5400 rpm) rotational speed.
B)Interface speed
Somewhat important. The difference in speed between an ATA/100 and ATA/133 drive won't be noticeable to most users. To get maximum performance from your hard drive, its interface speed must match the interface speed of your PC, or you must install an interface card that matches the speed of the new drive.
C)Seek speed (seek time in ms)
A minor consideration. Average seek speed (measured in milliseconds) is how fast, on average, drives can find a particular piece of data. For most people, the differences in everyday use will be negligible. The exception is when many relatively small and scattered bits of data need to be assembled, such as when copying large folders full of many small files.
D)Buffer size
A minor consideration. The buffer is a memory cache on the drive where data is temporarily stored in anticipation of the next likely request of the PC's processor. Because random-access memory is considerably faster than mechanical rotating storage, it can speed performance. The latest drives for desktop PCs have generous buffers of 2MB or larger, more than adequate for typical use.
2)
http://computer.howstuffworks.com/hard-disk1.htm
There are two ways to measure the performance of a hard disk:
Data rate - The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common.
Seek time - The seek time is the amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are common.
3)
http://squid-docs.sourceforge.net/latest/html/c21.html#AEN49
Hard Disks FOR SQUID CACHING PROXY :)
There are numerous things to consider when buying disks. Earlier on we mentioned the importance of disks with a fast random-seek time, and with high sustained-throughput. Having the world's fastest drive is not useful, though, if it holds a tiny amount of data. To cache effectively you need disks that can hold a significant amount of downloaded data, but that are fast enough to not slow your cache to a crawl.
Seek time is one of the most important considerations if your cache is going to be loaded. If you have a look at a disk's documentation there is normally a random seek time figure. The smaller this value the better: it is the average time that the disk's heads take to move from a random track to another (in milliseconds). Operating systems do all sorts of interesting things (which are not covered here) to attempt to speed up disk access times: waiting for disks can slow a machine down dramatically.
Sorry for the long post.
Originally posted by froilanr
Off-topic!
SCSI Hardisk w/ 10,000 RPM is faster than a SCSI w/ 7, 200 RPM.
----------------------------------
Posted by RiderDriver:
Not necessarily true. RPM tell you have fast the disk is spinning, not the ACCESS time to get the DATA.
sorry, just had to say something about that.
__________________
RiderDriver,
I dont agree! RPM specifications of a hardisk helps to read and write data faster. So the bigger the RPM the better, but it's not
necessary in some applications.
I think you are saying the Hardisk specification SEEK TIME. The smaller the SEEK TIME (in ms), the faster it can access data.
Here's the proof why RPM specification is important!
Also some important informations when choosing or buying hardisk.:)
SOURCES:
1)
http://computer.howstuffworks.com/framed.htm?parent=hard-disk.htm&url=http://www.pcworld.com/reviews/bguide/0,guid,20,page,1,00.asp
A) Rotational speed
5400 rpm
5400 rpm to 7200 rpm
Somewhat important. Faster rotational speed means the drive reads and writes data faster. Rpm is more important if you use a PC for video or multimedia applications: Differences in rpm don't make a noticeable difference for tasks such as word processing or Web surfing. The largest drives often have the slower (5400 rpm) rotational speed.
B)Interface speed
Somewhat important. The difference in speed between an ATA/100 and ATA/133 drive won't be noticeable to most users. To get maximum performance from your hard drive, its interface speed must match the interface speed of your PC, or you must install an interface card that matches the speed of the new drive.
C)Seek speed (seek time in ms)
A minor consideration. Average seek speed (measured in milliseconds) is how fast, on average, drives can find a particular piece of data. For most people, the differences in everyday use will be negligible. The exception is when many relatively small and scattered bits of data need to be assembled, such as when copying large folders full of many small files.
D)Buffer size
A minor consideration. The buffer is a memory cache on the drive where data is temporarily stored in anticipation of the next likely request of the PC's processor. Because random-access memory is considerably faster than mechanical rotating storage, it can speed performance. The latest drives for desktop PCs have generous buffers of 2MB or larger, more than adequate for typical use.
2)
http://computer.howstuffworks.com/hard-disk1.htm
There are two ways to measure the performance of a hard disk:
Data rate - The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common.
Seek time - The seek time is the amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are common.
3)
http://squid-docs.sourceforge.net/latest/html/c21.html#AEN49
Hard Disks FOR SQUID CACHING PROXY :)
There are numerous things to consider when buying disks. Earlier on we mentioned the importance of disks with a fast random-seek time, and with high sustained-throughput. Having the world's fastest drive is not useful, though, if it holds a tiny amount of data. To cache effectively you need disks that can hold a significant amount of downloaded data, but that are fast enough to not slow your cache to a crawl.
Seek time is one of the most important considerations if your cache is going to be loaded. If you have a look at a disk's documentation there is normally a random seek time figure. The smaller this value the better: it is the average time that the disk's heads take to move from a random track to another (in milliseconds). Operating systems do all sorts of interesting things (which are not covered here) to attempt to speed up disk access times: waiting for disks can slow a machine down dramatically.
Sorry for the long post.