Performance monitoring help needed.
 

How would i check for following?
open ports in my linux machine.
Hard disk read speed.
Hard disk write speed.

Clarify please: open as in
a) something listening
b) not actively blocked by iptables

Clarify please:
a) current write speed on a disk
b) a measurement of the drives max performance

Clarify please: (SEE ABOVE)



Cheers,
Tink

I didnt thought of the options you have provided.
It will be better if i can get all answers you specified here.

nmap localhost
netstat -antlp

hdparm -tT /dev/sda <= your HDD
hdparm -I /dev/sda | grep speed

read command's man page for more information

hdparm has a more serious drawback: it can crash a computer and make data on its disk inaccessible if certain parameters are misused. Out of approximately sixty-seven parameters, several are dangerous and could result in "massive filesystem corruption" when used indiscriminately.
wiki source http://en.wikipedia.org/wiki/Hdparm

Yes you are right, but when you use any DANGEROUS parameters.In man page they define which parameter is DANGEROUS or VERY DANGEROUS. It crash computer only when you use/misuse any dangerous parameters.It depends on you what parameter you want to use.

hdparm's results are all fog & mirrors anyway; if you want to
get a realistic result for multi-user, multi-tasking OS you'll
have to resort to bonnie or bonnie++.


Cheers,
Tink

Being a novice user to linux i m little unaware of most of the solution given in reply to my original post.
However i m surprise as there is not a simple command to check the read and write speed of the harddisk.
One of my mate is suggesting to create a file using dd command and check how much time it takes to create a 1 gb file .
I think this has a little sense however i would also like to take your reviews about the same.

This is how i m going to test the write speed.

'For write
This will create a 45 gb file in X seconds.
by calculating Diskspace in kb / Second i will get the actual write speed in kb/s .

Disk read and write speed.
 

Being a novice user to linux i m little unaware of how would i check disk read write speed.

One of my mate is suggesting to create a file using dd command and check how much time it takes to create a 30 gb file .
I think this has a little sense however i would also like to take your reviews about the same.

This is how i m going to test the write speed.

'For write
This will create a 30 gb file in X seconds.
by calculating Diskspace in kb / Second i will get the actual write speed in kb/s .
Code:

As I said above: use bonnie++

Using dd & a linear write or read process is as artificial
as using hdparm, and will give you fairly little indication
of what you'll see in a multi-user, multi-tasking environment
as far as usage patterns go.



Cheers,
Tink

P.S.: I took the liberty to tack your new post onto the old
thread with almost identical wording in the last post.