Sign in with
Sign up | Sign in
Your question

I/O performance,throughput,sequential transfer rates

Last response: in Storage
Share
August 3, 2009 12:52:49 PM

I/O performance
throughput
sequential transfer rates
.
.
.

How can i find out each one of these mostly effects what?
(i'm a newbie and i just want to know for example which is most effective in running apps as fast as possible and so on)
is there a way not to explain them technicaly but how do they effect real working?
a c 127 G Storage
August 3, 2009 4:45:17 PM

I/O performance is performance related to storage, so HDD/SDD or even CD/DVD performance.

Throughput is the amount of raw data that can be processed, often sequentially like one big file. The throughput of copying that file would be 40MB/s for example, or 40 megabytes per second.

STR; sequential transfer rate, is the "maximum" speed of the SSD/HDD when files are read or written in sequential order.

Opposite to STR there is Random I/O. This involves alot of "seeking" for which HDDs are heavily penalized. However since SSDs don't have to "seek" they will be very fast with Random I/O. Random I/O performance is often expressed in IOps, or I/O operations per second. For example, an SSD can do up to 35.000 random read IOps, while HDDs can barely reach 100 IOps. Even 15.000rpm disks only score 200 IOps here.

Which is important?

Thoughput: for large files/copying
Random I/O: for booting/application loading (virtually everything when you hear your HDD seeking alot)

So Random I/O performance rated in IOps is much more than sequential I/O performance ("throughput") rated in MB/s. Hope this clears your question. :) 
!