Unix/Linux Go Back    


UNIX for Dummies Questions & Answers This forum is closed for new posts. Please post beginner questions to learn unix and learn linux in this forum UNIX for Beginners Questions & Answers

Determining Disk Speed

UNIX for Dummies Questions & Answers


 
 
Thread Tools Search this Thread Display Modes
    #1  
Old Unix and Linux 10-04-2012
mojoman mojoman is offline
Registered User
 
Join Date: Nov 2007
Last Activity: 9 November 2016, 4:24 PM EST
Posts: 250
Thanks: 0
Thanked 1 Time in 1 Post
Determining Disk Speed

Hi,

I went to a computer store and the salesman sold me a SATA cable and told me that all SATA cables are the same. Another salesman at a different store told me a cable rated for SATA 2, which I bought, MIGHT work as well as one rate for SATA 3 but it is not guaranteed. I decided to run a speed test on my SSD drive to check the results.


Code:
dd if=/dev/zero of=/tmp/output.img bs=8k count=256k
262144+0 records in
262144+0 records out
2147483648 bytes (2.1 GB) copied, 0.530362 s, 4.0 GB/s




Code:
for i in 1 2 3; do hdparm -tT /dev/sda; done

/dev/sda:
 Timing cached reads:   27076 MB in  2.00 seconds = 13556.06 MB/sec
 Timing buffered disk reads: 1244 MB in  3.00 seconds = 414.46 MB/sec

/dev/sda:
 Timing cached reads:   28788 MB in  2.00 seconds = 14414.45 MB/sec
 Timing buffered disk reads: 1244 MB in  3.00 seconds = 414.48 MB/sec

/dev/sda:
 Timing cached reads:   27958 MB in  2.00 seconds = 13998.11 MB/sec
 Timing buffered disk reads: 1248 MB in  3.00 seconds = 415.91 MB/sec
[root@mohit-speed-daemon ~]#

I can verify from dmesg and /var/log/messages analysis that I am connected a 6.0gbps. Are my results consistent with that type of connection?
Sponsored Links
    #2  
Old Unix and Linux 10-04-2012
rdrtx1 rdrtx1 is offline
Registered User
 
Join Date: Sep 2012
Last Activity: 30 November 2016, 11:31 AM EST
Location: Houston, Texas, USA
Posts: 873
Thanks: 0
Thanked 299 Times in 286 Posts

Code:
sudo hdparm -I /dev/sda | grep -i speed

where /dev/sda : Hard disk device file
Sponsored Links
    #3  
Old Unix and Linux 10-04-2012
mojoman mojoman is offline
Registered User
 
Join Date: Nov 2007
Last Activity: 9 November 2016, 4:24 PM EST
Posts: 250
Thanks: 0
Thanked 1 Time in 1 Post
That command will just tell me that these speeds are supported.
I ran the read/write tests to see what speed it is actually operating at.
I want to know if these speeds are acceptable for a 6.0gbps drive?
    #4  
Old Unix and Linux 10-05-2012
Corona688 Corona688 is offline Forum Staff  
Mead Rotor
 
Join Date: Aug 2005
Last Activity: 2 December 2016, 5:18 PM EST
Location: Saskatchewan
Posts: 21,658
Thanks: 1,008
Thanked 3,980 Times in 3,697 Posts
The maximum transfer rate of SATA 2 is, ideally, around 300 megabytes per second. You're beating that by 30% in the real world so it really does look like you're getting SATA 3 speeds.

Just because a drive uses a SATA 3 port doesn't mean it's capable of its full 600 megabytes per second, of course. Whether you're reaching the true maximum speed of your drive, I can't say without knowing what it is and looking in its manual. The limits of your southbridge and memory are also important.

Last edited by Corona688; 10-05-2012 at 01:22 PM..
Sponsored Links
 

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Linux More UNIX and Linux Forum Topics You Might Find Helpful
Thread Thread Starter Forum Replies Last Post
Disk read and write speed. pinga123 Filesystems, Disks and Memory 5 08-17-2010 07:05 PM
data from blktrace: read speed V.S. write speed W.C.C Filesystems, Disks and Memory 1 10-26-2009 10:42 AM
AIX - Determining link speed karlgo AIX 3 08-02-2005 03:52 AM
determining ethernet port speed in solaris xyyz UNIX for Advanced & Expert Users 7 11-12-2003 02:11 AM



All times are GMT -4. The time now is 02:01 AM.