Solved

Hard Drive - Seek Time, Write Time, and Latency - Looking for clarification

Posted on 2013-01-30
4
1,097 Views
Last Modified: 2013-02-24
These are the Seek Time, Write Time, and Latency specs for my old hard drive (Seagate Momentus 7200.4 ST9500420ASG 500GB 7200 RPM).

Average Seek Time = 11ms
Average Write Time = 13ms
Average Latency = 4.17ms

What's the total Read Time? Here's my guess:
Average Total Read Time = Average Seek Time + Average Latency
Is this correct?

What's the total Write Time? Here's my guess:
Average Write Time = Average Write Time  + Average Latency
Is this correct? Or, do I omit Latency because it's already included in the Average Write Time?
0
Comment
Question by:jdana
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
4 Comments
 
LVL 30

Accepted Solution

by:
Duncan Meyers earned 163 total points
ID: 38836766
Yes - latency is typically one half of a rotation. Total read time should include settling time and the time to read a sector. Your calculation for write time is correct assuming that the specs have included seek time in the write time. If not, you need to add average seek time.

It's quite a slow drive. A 10k enterprise drive has latency around 3.5mS and average seek times around 2.5mS.
0
 
LVL 92

Assisted Solution

by:nobus
nobus earned 162 total points
ID: 38838686
0
 

Author Closing Comment

by:jdana
ID: 38923005
Thanks!
0
 
LVL 30

Expert Comment

by:Duncan Meyers
ID: 38923999
Thanks! Glad I could help.
0

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In this article we will learn how to backup a VMware farm using Nakivo Backup & Replication. In this tutorial we will install the software on a Windows 2012 R2 Server.
Many businesses neglect disaster recovery and treat it as an after-thought. I can tell you first hand that data will be lost, hard drives die, servers will be hacked, and careless (or malicious) employees can ruin your data.
This video Micro Tutorial explains how to clone a hard drive using a commercial software product for Windows systems called Casper from Future Systems Solutions (FSS). Cloning makes an exact, complete copy of one hard disk drive (HDD) onto another d…
Finding and deleting duplicate (picture) files can be a time consuming task. My wife and I, our three kids and their families all share one dilemma: Managing our pictures. Between desktops, laptops, phones, tablets, and cameras; over the last decade…

628 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question