Linux - SoftwareThis forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.
Notices
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Get a virtual cloud desktop with the Linux distro that you want in less than five minutes with Shells! With over 10 pre-installed distros to choose from, the worry-free installation life is here! Whether you are a digital nomad or just looking for flexibility, Shells can put your Linux machine on the device that you want to use.
Exclusive for LQ members, get up to 45% off per month. Click here for more info.
hi
I wanted to evaluate linux i/o scheduler performance.
presently aI am trying with DD command for this perpose.
Plz let me know any other ways to evaluate performance of LINUX I/O scheduler.
I wanted to find out
1) maximum allowable streams
2)response time
Linux has multiple, dynamically configurable I/O schedulers (noop, anticipatory, deadline, cfq). The CFQ scheduler is currently the default, and there are several configuration options. You might want to start by reading this. There are also several books you should check out (1, 2). This is a very non-trivial topic.
dd is an aweful predictor of real world I/O. About the only thing that comes close (in I/O profile) is ripping/burning DVDs.
I/O response times are not available - hence the usage of external (measureable) metrics such as thruput and trans/sec.
You'd better determine your (system-wide) I/O and construct test scenarios accordingly.
Things may change on you as well - RAID cards, disk cache, I/O channels ...
Nothing is ever as easy as it may first look.
thank you macemoneta,
thanku for giving me nice stuffs.
I am currntly considering deadline scheduler.
as i know now 1)Number of streams
2)response time
3)throughput
are parameters which are messure of performance of deadline I/O schduler.
I am using DD command to check the performance.
plz let me know any other parameters are there to consider as messure of performance?
and is any other way to messure performance other than dd ??
dd is an aweful predictor of real world I/O. About the only thing that comes close (in I/O profile) is ripping/burning DVDs.
I/O response times are not available - hence the usage of external (measureable) metrics such as thruput and trans/sec.
You'd better determine your (system-wide) I/O and construct test scenarios accordingly.
Things may change on you as well - RAID cards, disk cache, I/O channels ...
Nothing is ever as easy as it may first look.
we can use read and write system calls along with seek. why DD preffered?
Why are you using dd ???. You mentioned you were using dd for your tests - I was suggesting it wasn't a reasonable scenario.
Since i found in some white papers they used DD.
Now i am looking for more accurate performance, plz tell me other ways..............
read/write and seek will serve this purpouse??????????
LinuxQuestions.org is looking for people interested in writing
Editorials, Articles, Reviews, and more. If you'd like to contribute
content, let us know.
