Test Subchannel Instruction

TSCH simulation by CP is costly, so use QSCH (Quiz Subchannel) where ever possible.

Shopping without the List

Too often we write software that performs poorly. If we acted the same way when we went grocery shopping, we'd drive to the store and get just one item at a time. We'd return home, cross that item off the list, and then drive back to the store for the next item.

Right Answer

"The right answer to the wrong question, is still the wrong answer." - Virg Meredith

Nothing Changed

If someone tells me they ran a program once and it ran fine and then they ran it again without changing anything and it ran much slower, I ask them "If you didn't change anything, why did you run it again." - Virg Meredith (IBM Performance Great)

Dormant List

• Ducks
• Welcome
• Astro Turf
• Woven
• Dog chewing on Boot

Oh, Dormant list, I thought you said Door Mat list.

Performance Definition

Performance: A statement of the speed at which a computer system works. Or rather, might work under certain circumstances. Or was rumored to be working about a month ago.

The birds and the Mice

The early bird catches the worm, but the second mouse gets the cheese.

Response Time vs. Throughput

I once had to explain to some planning folks how we could be getting better response time, but worse throughput. I told them the same way the shortest route in terms of time for a trip might require more gas and cover more miles than a route that takes a longer time.

Box vs. Fence

A little ditty I got from the Level 2 guys to remember whether it is the hardware or software that boxed or fenced a device.

• 2-3-4-5
• 2 letters - 3 letters - 4 letters - 5 letters
• We - Box - They - Fence

Meaning VM boxes a device, Hardware fences a device. So if you are a hardware person, you'll have to get your own ditty to remember.