Really? I Need A Mainframe?

On the twitters today I came across a tweet by @mreferre pointing to a blog about mainframes aptly named The Mainframe Blog. The catchphrase for that blog seems to be “blank needs a mainframe”, with links to various outages like those by AWS. So my first thought is…

Are you f#@%ing kidding me?

Actually, no, that wasn’t my first thought. My first thought was Beeper King, Liz Lemon’s boyfriend’s pager business from 30-Rock. A pager store, in the 21st century.

I cut my teeth in the mid to late 90s on the Unix systems that usurped the mainframe. I even took a mainframe class at IBM’s headquarters, installing Linux on LPARS (IBM came out with the first hypervisor in the 60’s after all). It was a weird, bizarre experience. 31-bit Linux. That’s not a typo. 31-bit. And it was painfully slow. Mainframes have a reputation for power, but really the power that they have isn’t in the processors. Or RAM for that matter. Take a look at the specs for the new IBM zEnterprise 114 mainframe system.

10 processors (a variation of the Power7s I believe, fast but not game changing processors) and 256 GB of RAID’d RAM. Only 256 GB and 10 CPUs in a full rack? I can get 512 GB and 2 CPUs into a single blade with a Cisco UCS B230 M2 blade, 8 slots per chassis for 4 TB and 16 CPUs in a chassis, and 6 chassis in a rack. That’s 24 TB of RAM versus 256 GB of RAM, 10 CPUs versus 96 CPUs (960 cores with the new Intel E7’s). 10 CPUs and 256 GB is also the max, so you know it’ll cost an arm and a leg.

I admit, I’m not very schooled on mainframes, and I have minimal stick time on them, but they don’t seem as all that flexible. They seem to me to be designed to do a few very important tasks very reliably (not necessarily fast).  Something like keeping track of money, or airline reservations. But these days even those systems are typically front ended by a web application, not a TN3720 terminal. Given the processing and memory limitations, I don’t think mainframes could possibly handle running web applications in any kind of cost effective or scalable way.

Add to that the cost of mainframes (wheelbarrows of cash), and a host of proprietary storage and networking connections that also cost an arm and a leg. Also, last time I checked, mainframes still booted via a virtual punchcard. Seriously. Most mainframes will have an IBM/Lenovo laptop plugged into them at all times because they can’t boot without them. Probably not any reason not to go mainframe, but it is strange.

Another reason not to trust mainframes. If a computerized voice asks you to play a game, you say no.

Besides, I don’t think “blank needs a mainframe” is usable in all cases. You could say the same thing about Air New Zealand’s outage in 2009, but they had a mainframe. Run by IBM.

I could be wrong about a lot of things in this article, but I just don’t see mainframes as a viable data center technology except for speciality cases. But maybe that’s just me (and everyone else I know).

One Response to Really? I Need A Mainframe?

  1. Traditionally mainframes had superior I/O subsystems as compared to Unix boxes. Running queued transaction-oriented workload or database servers made perfect sense (although even that advantage is lost now that RAM is so cheap a blade server can cache most of the database indices).

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