Rich Frangiamore

Systems Admin

Two Buck Chuck or How I Had My Load Balancing Epiphany

Last night, I detoured over to my very favorite purveyor of groceries, Trader Joe’s, on my commute home. This is a new-ish location, in Clarendon, just across the street from the Metro station. It being rush hour, the checkout line was massive. I finished my list by grabbing a five dollar bottle of Zinfandel (don’t judge me) and got in line. Servers

It was then that I had an epiphany. This TJ’s, unlike the other locations around Arlington which have individual lines for each register, has a long row of vertically stacked registers with one huge line. When a register is ready for another customer, an expediter waves you to the open spot. I thought to myself, “Wow, the throughput is faster than the other location. I’m not at risk of getting stuck behind some person who demands that the butternut squash is ten cents cheaper, then spends 5 minutes digging through her purse for a checkbook. Hey, this is almost like load balancing on VMware.”

The analogy is to one of my favorite topics, hardware virtualization. Two of the biggest features of VMware’s Enterprise Plus version of vSphere (i.e. the Cadillac of virtualization) are Storage Distributed Resource Scheduler and Storage I/O Control . These two tidbits, in a nutshell, let you prioritize certain I/O traffic to your perferred VM’s, as well as perform load balancing on pools of datastore volumes.

If a bottleneck forms to the storage array containing the virtual disk of a top-priority server, the product will prioritize throughput to that server, and allocate additional resources from other storage in the pool.  You can even hot add additional storage to a storage pool and have the additional space and performance dynamically allocated where it is needed the most.  It’s the holy grail of virtual storage.  Combined with other features like vMotion and Storage vMotion, I often have a Tim “The Toolman” Taylor moment when I think about the raw power of this solution. It’s why VMware wears the crown in the industry.

Now, if only I could have an epiphany about something that hasn’t been invented yet…

Have you had any epiphanies about web tools while out in the world? What have you discovered?