Lewan Technology Blog

Nobody likes to wait. And time spent waiting for an application to respond is, at best, wasted staff time, and at worst, lost revenue or lost customers. To meet this demand for high performance, always-on infrastructures, one of the most exciting partnerships we’re able to offer our clients is Nimble Storage.

Our customers already rave about the simplicity and performance Nimble has brought to their infrastructures with hybrid storage arrays, and now this week, Nimble has announced a new family of storage arrays built with only flash drives, the Predictive All Flash Array (AFA).

Is your default VMware E1000 network interface (NIC) installed in a virtual machine causing problems with performance?

The best practice from VMware is to use the VMXNET3 Virtual NIC unless there is a specific driver or compatibility reason where it cannot be used. In many cases, however, the E1000 has been installed, since it is the default.

I'll start by answering the title question first. IOP is an acronym standing for Input Output Operation. It does seem like it should be IOO, but that's just not the way it worked out.

A related fact to note: we generally talk either about total IOPs for a given task, or we talk about a rate - IOPs per Second typically, noted as IOPS with a capital "S". And with that, the Wikipedia portion of today's discussion is complete. Let's move on to why we care about IOPs...

Today's topic - Disk Performance. A warning to the squeamish...Math ahead.

Throughput refers to the amount of data read or written per unit of time. Generally measured in units like Megabytes per second (MB/s), or Gigabytes per Hours (GB/h). Often when dealing with networks we see Kilobits per second (Kb/s) or Megabits per second (Mb/s). Note that the abbreviations of some of those units look similar, pay attention to the capitalization because the differences are a factor of at least 8x.

I've told several groups I've spoken to recently that "disk storage hasn't gotten faster in 15 years". Often that statement is met with some disbelief. So let me explain my reasoning...

Traditionally businesses take on huge investments in their WAN and at many times the cost of upgrading to keep up with the network demands or moving to a new provider is painful and typically becomes a long drown out project that ties up business time, money and resources. This is where IWAN helps; this solution is transparent to the underlying network that is runs on. Thus, making the corporate network an overlay to the underlying ISP’s network(s). At the same time simplifying the overall WAN architecture and providing a flexible, consistent management domain that allows businesses to be provider agnostic and bring branch offices online in days rather than weeks.

If there are disk array or networking issues in VMware ESX 3.x or vSphere, some virtual machines (VMs) may appear in the vSphere Client as being Invalid and are greyed out. The following steps will fix this issue.