Clogged Device Drain? Use Your Data Snake!

Lee

By Lee LaFresePlunger

Have you ever run into high I/O response times that simply defy explanation? You can’t find anything wrong with your storage to explain why performance is degraded. It could be a classic “slow drain device” condition. Unfortunately, you can’t just call the data plumbers to clean it out! What is a storage handyman to do?

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Noisy Neighbors: Finding Root Cause of Performance Issues in IBM SVC Environments

By Jim SedgwickNoisy Neighbors

At some point or another, we have probably all experienced noisy neighbors, either at home, at work, or at school. There are just some people who don’t seem to understand the negative effect their loudness has on everyone around them.

Our storage environments also have these “noisy neighbors” whose presence or actions disrupt the performance of the rest of the storage environment. In this case, we’re going to take a look at an SVC all flash storage pool called EP-FLASH_3. Just a few bad LUNs have a profound effect on the I/O experience of the entire IBM Spectrum Virtualize (SVC) environment.

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How to Diagnose IBM SVC/Storwize V7000 (Spectrum Virtualize) Replication Performance Issues: Part 2 Diagnostics

Brett

By Brett Allison

 

In part 1 of this blog series we talked about how to select your SVC/V7000, replication technology that matches your business requirements, or more likely, your budget.

Now we need to think about how you can monitor and diagnose SVC/V7000 performance issues that may be caused by replication. I run into SVC/V7000 replication issues quite frequently, and have found that not all monitoring and diagnostic tools provide a comprehensive picture of SVC/V7000 replication. Further complicating matters, the nature of the technology you have selected will influence expectations and approach to problem determination.

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How to Choose the Best IBM SVC/Storwize V7000 (Spectrum Virtualize) Replication Technology: Part I Introduction

Brett

By Brett Allison

Disaster Recovery Plan

Choosing the wrong V7000/SVC replication technology can put your entire availability strategy at risk.

For most customers, there seems to be a bit of a mystery in how replication works. On the surface, it is simple. Data is written to a primary copy and either synchronously or asynchronously copied to a secondary location with the expectation that a loss of data at the primary site would result in minimal data loss and a very minimal recovery effort.

There are several types of replication, and each type has its nuances. Each of these technologies should be evaluated in light of the following business requirements:

1. Recovery Point Objective (RPO): This is the amount of data loss expressed in time units (typically minutes) that you will lose should there be a failover to the secondary site.   Continue reading