New Customer, new ERP Implementation… and the inevitable question!

We are about to buy this hardware, is it suitable? The trouble with that question is suitable for what? What you need now for that peak twenty minutes as you generate statements or do the payment run? Or for what you might need in the future because it’s got to last you at least five years?

If you run Microsoft Dynamics NAV on premise then all but the smallest user counts will one day come across performance issues. As data volumes and user counts grow this becomes something we have to pay more attention to if the impressive, instant speed users become used to initially is to be maintained. This is not restricted to Dynamics applications, but is true for any database system. The principles we outline below for keeping the system optimal apply to any such application, especially if based on Microsoft’s SQL Server database platform.

By far the best option are the newish SSD (solid state discs) that are made up of electronic chips. The trouble is that these chips only support a number of writes to the same place before they burn out, and while this will be years on a normal laptop or PC, on a database server with lots of people feeding revised data all the time – it can happen very quickly. For this reason the SSD’s suitable for database servers are expensive basically because they have to have lots of redundancy, so when an area burns out it can move the information to a spare area.

The older type still use mechanical spinning disks to encode magnetic data. These have read/write heads that go across the disk to the correct track as the sector spins round. That means you have what we call latency, the delay while the disk gets itself into the right position to read or write the data you need.

This latency means that performance is improved by having lots of smaller disks rather than a few large ones. The read/write heads cannot be in multiple places at the same time, so having two on two disks rather than one big one gives twice as much chance of it being positioned to retrieve the data you need. Similarly buying faster spinning disks that spin 15,000 times a minute means that data comes round under the heads quicker than on those slower 7,200rpm drives.

What those disks are connected to is also critically important. There will be times when the communication channel to the disks will be saturated so the faster and wider it is, the better. If the disks are the carparks then the disk subsystem are the roads from the car parks to the motorway. A road system that allows all the carparks to both park and leave without getting is each other’s way and at motorway speed is what you need. That means either a fast SCSI or better still a SAN (Storage Area Network) based system.

With thanks to James Crowter at Technology Management on who’s original article this is (very) largely based!

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Post by Stephen Malloy

Talk to me if you’re considering a business solution. If I don’t know the answer, I will know someone who does.