I attended a very interesting presentation from the CIO of a large retail firm, the other day, about his experiences with Linux, and particularly Linux running on an IBM mainframe (z/Linux).
This company has been involved with Linux for around 3 years, and I picked up a number of key points.
Basically, the company has been moving some workloads from Intel-based Microsoft servers to the z/Linux environment. One of the first points I picked up was the improved utilization of resources, with corresponding cost savings. Instead of heaving a bank of servers each running at 10% or so utilization, the workloads all ran on the mainframe. This avoids a lot of wasted capacity. What was also extremely interesting was that the company ran the two systems side by side for four months to validate the solution was working correctly, and whereas the server-based system had a number of unplanned outages and failures, the Linux system was 100% reliable.
Another salient point was that in each store, IT support for the store’s needs are provided by a local Linux server. This has the byproduct in the new environment of providing a fail-over environment in z/Linux on the mainframe – because the two operating system environments are the same, it is relatively easy to do this.
An important observation from the CIO was that Linux is definitely not free. However, this company has found a number of major benefits in cost terms:
- S/W license costs (eg system software) are reduced
- One resource provides support (vs 1 per 12 servers in old environment)
- Capital expenditure is reduced (better utilization, as discussed)
In addition to these cost benefits, the CIO is able to respond to new demands more quickly because a new server request is satisfied by a logical reconfiguration on the mainframe rather than having to get approval for and purchase a new server.
The summary was that the big hitters for this particular company were TCO (total cost of ownership) reduction and availability improvements. However, one final point is worth mentioning. The CIO pointed out that the company is not expecting Linux to supplant Windows. It is true that Open Office is being trialled in some places, but his expectation is that there is a place for both environments.