Bend in the Weather (Entries tagged as failure)

When customer profiling and targeted advertising goes wrong

mbottrell@gmail.com (Matt) — Sun, 25 Jul 2010 10:10:00 +1000

Don't get me wrong... I love a bargain as much as the next guy or girl.

What I don't like however is when a computer system is implemented with little regard and isn't actively checked by a human.
It's one way to make your company look like a jack-ass.

Sorry Woolworths - you've landed yourself in such a category.

Most Australian supermarket shoppers are aware of the fuel discounts offered by Coles and Woolworths, which can slice anything from $0.03 - $0.20 per litre of the cost of your fuel. Something that's always welcome by motorists.

It's the only reason I have an everyday rewards card. Fuel discounts add up over time, even more so for myself, as I drive with LPG the majority of the time, so $0.20 off per litre on LPG is quite substantial.

During the months of April and May Woolies decided that for 8 weeks straight I would like to buy wine. I'm not talking 1 bottle either. Most 'deals' require a purchase of 6 or more bottles in a given purchase.

A sample of the Email contents is included below:

To be honest, I love a good drop of red. Probably more so than the average punter. (We normally have a few dozen on hand in the house). At the end of March I had let our stocks go down over a period of time so had restocked. This seems to have triggered their rewards system to pester me for the next 8 weeks straight. No fuel offers (which was the main selling point of the card), nor any other offer... just grog.

At 6 bottles minimum per Email over 8 weeks, anyone reading my Email from Woolworths, would think I'm an alcoholic!

The crazy thing... It backfired.
I didn't buy any wine during that period. (As I had just restocked my levels.) This form of marketing happens 'after the fact', and as such it fails. If I have already made a bulk purchase, why would I wish to repeat it shortly after, and every week for a period of 8 weeks?

Woolworths reward system needs looking at. (As does Coles for that matter). It would be more beneficial to flag such bulk purchases of your customers, then look at sending it out 'specials' say every 3,6 or 12 months... you're likely to have a bigger uptake. I can't see my car dealership sending out a "buy a brand new car" Emails if I had just taken delivery of a new vehicle.

Certainly for everyday staples, it would be nice to have these filter through regularly. However don't see these, like 25% off either Meat, Fruit or Vegies for a week. It seems to be items like Coca-Cola, Alcohol and other non-essentials. I'm not surprised though... the supermarkets know we need staples.. and are trying to increase our trolley sizes by teasing us into buying these non-basic item.

Certainly I do hope that Woolworths and Coles both learn that their average shopper has the intelligence above that of a broken trolley wheel, as the current marketing strategies to date are quite insulting.

tzdata changelog

mbottrell@gmail.com (Matt) — Sun, 18 Oct 2009 08:40:00 +1100

Often changelogs have important information on why a package was updated. Other times, they are just humorous:

tzdata (2009n-0ubuntu0.9.04.1) jaunty-proposed; urgency=low

* Add argentinas-dst-2009.diff: Disable DST switch for Argentina tomorrow,
as the Argentina government decided yesterday. Careful planning is boring.
Thanks to Margarita Manterola for the patch! (LP: #453165)

-- Martin Pitt Sat, 17 Oct 2009 14:22:39 +0200

Perspective

mbottrell@gmail.com (Matt) — Sat, 03 Oct 2009 13:48:00 +1000

MX is a free commuter magazine published in Brisbane, Melbourne and Sydney.

A regular feature, they ask commuters a question.

Given their time again, I think John and Claire would answer differently.

Source: PhotoBasement

Presenting Pr0n.

mbottrell@gmail.com (Matt) — Fri, 15 May 2009 02:49:00 +1000

I read Jacinta's post and have to agree with the statements she made.
I'm a red blooded male with crazy hormones running around my body like the next person, yet I know there is a time and a place for such things.

Let's put it in clear context. "Pr0n has no place in a technical conference presentation."

One wouldn't show pr0n related images to their own grandmother or a stranger in the street.
Use this 'stranger in the street' or 'my own grandmother' as a general guide if you are unsure.

If you feel the need to resort to showing such images, you need to ask why.
Is your presentation that dull you need to distract your audience?
Are your presentation skills that poor you need to resort to cheap stunts to keep your audience interested?
Is your knowledge on the given topic limited and needs attention to be misdirected away from the main discussion point?
Are you sure all your audience is of legal age? Being a technical conference doesn't mean there aren't minors present. Keep this in mind.
As a parent, I would be outraged if my teenage child attended such a conference to be subjected to pornographic images.

Playing the 'pr0n card' in a presentation shows a lack of maturity and disregard for your audiences intelligence.
It really isn't 'witty' at all and quite offensive.

Feel free to use humour in your presentation to liven it up, but keep it on a neutral topic and not one that is controversial.
Remember - your presentation is supposed to educate people to your point of view. You won't do this if it polarises your audience!

You would expect a backlash to your presentation if it contained anti-semitic or a white supremacist suggestions... expect the same with anything controversial.

If in doubt, why not run your presentation prior to the conference via the organisers. It's much easier cleaning up the slides prior to the presentation rather than the egg you'll have on your face.

RAIDing the RAID

mbottrell@gmail.com (Matt) — Sat, 18 Oct 2008 03:44:00 +1100

In a not to distant past Russell Coker wrote about RAID Issues and referred in part to a report containing data from 1,530,000 disks running at NetApp customer sites. (also available in PDF or Postscript)

Interesting reading, for sure - particularly if you run any large dataset and want to ensure it stays intact!

It prompted in the recesses of my memory a report compiled in February 2007 by Google. The report, 'Failure Trends in a Large Disk Drive Population' was a report presented at the USENIX (FAST '07) Conference.

The Google report looked at actual hardware failures of disk Google saw over several years. The numbers were crunched (Is there anything else Google does besides crunch large datasets?). Some interesting results popped out:

The disks studied where either SATA or PATA consumer-grade disks that were either 5400RPM or 7200RPM ranging in size from 80G to 400G and been commissioned from any time after 2001. - Interesting this is the same disks that many of us will find in our own machines. No Enterprise disks, SCSI or SAS disks in the study.
HDDs had a higher tendancy to fail at the start of their life or anything beyond >3 years of use.
Low or Heavy Utilization of the HDD resulted in greater loss then 'Medium use'.
Disks that had surface scan errors had a greater result of failure over the next 60 days.
HDDs in operating in cool temperature (15-30^oC) had much greater failure rate in the first 3 years. Whilst disks > 3 years had a greater failure rate with the higher the operating temperature. The ideal rate for running disks to minimise failure rate was 30-35^oC.
A disk that spends more than 50% of it's powered on time > 40^oC is a good indication of a possible problem.
SMART data analysis revealed that it is not a reliable way to determine if a disk is about to fail. 36% of all disk failure had no SMART errors. The disks that had SMART errors the majority where seek errors (~72%). So basically, expect to see seek errors, beyond that you appear to be running blind with SMART.

Looking at both the Google Report and the NetApp Storage Report some 'best practices' become apparent to ensure you minimise your data loss:

HDDs are mechanical devices. Expect failure and plan for it.
Attempt to operate disks in the 30 - 35^oC temperature range to extend their life.
Monitor disk temperatures. Extended periods where a disk temperature rises unexpectedly (ie: not under any additional load than normal), is often an early sign that failure is close at hand.
Attempt to purchase disks not from the same batch. This will avoid a common manufacturing fault taking your disks out at the same time. (Many storage companies will do that for you as part of their service.)
HDD failure follows the Bathtub curve. The 'right side' of the bath kicks in around 3 years. Getting life out of your HDDs beyond that is a bonus, treat it as such!
HDDs are cheap these days. Don't be cheap -- implement RAID-6 over RAID-5 as a matter of course. Ensure you use Double-parity on your RAID-6 implementation. You'll find most recent versions of RAID-6 implement double-parity as 'standard'. (NB: If using NetApp - it's coined as RAID-DP.) Some vendors even allow you to upgrade the storage firmware online if using RAID-6 with Double Parity (NetApp for example has this feature).
Hot-Spares in your RAID-6 array is a very good idea. For the cost of the array consider it an insurance policy against the dreaded multiple disk failure which could potentially toast your array.
How important is your data? Can you put a cost on it? If the cost of replacement is extreme, consider redundancy options. This could include: Implementing RAID-60 (or RAID-6+0), archive/backup solutions, or even a total Disaster Recovery (DR) solution.
Air flow around an array unit is critical. Don't cram your arrays in a fully populated rack, as minimal air-flow will ensure. This will add to the HDD temperatures and general storage enclosure. Remember you're aiming to keep your disks at 30-35^oC.
Keep a logbook of when each drive was added/replaced. You know that 18 month disk then is less likely to fail than that disk that has been whirring away for 5 years. Record size, manufacturer and model/run. You may see some 'patterns' emerge in your own failure rates that will help with additional purchase decisions (ie: particular makes/models to avoid!)
Perform regular 'scans' or 'checks' of your HDD health, knowing the current state of disks allows you to plan for the inevitable failure.

Other tips I've picked up over the years looking after Enterprise systems attached to large storage arrays:

There is a reason that the ASX demands that publicly listed companies with 'mission critical' services for the public (items such as water supply, electricity/gas, and telecommunications) MUST ensure their 'mission criticial' applications have full Disaster Recovery operation on hot-standy.
Don't cut corners and not implement items like HotSpares and Double Parity. When you have a drive failure (not if), you'll be glade you spent that little bit extra on it.
A well planned storage solution should have drive failures, it shouldn't have storage failures. (Don't tell Sun/Internode that!)
Ensure you have clean-filtered power. Don't assume it. Power voltage fluctuations and disk writes don't play nicely.
Don't put all your eggs in one basket. Bad things do happen (I won't mention Internode again). Spreading your data out over multiple storage arrays helps add another level of redundancy. This is a GoodThing^TM
It's never a bad idea to have spare disks in storage waiting for that inevitable failure, rather than relying on a vendor to have your disk capacity/model available. Every day that dead disk isn't replaced you are putting your array at risk.
Look after your disks and arrays, and they generally will look after you (ie: ensuring you don't spend countless hours in the early mornings attempting to recover the unrecoverable!)

Above all, may your next disk failure not be a complete failure.

I'm interested to hear others stories, experiences and ideas that they have put in place to keep their data nice and cosy and their HDDs whirring in a constant and reliable state. Feel free to drop me a comment.

As a side note: I've been putting RAID-1 in place on my desktop machines as disk prices are so cheap now over the past 18 months. For the price of a few hundred dollars why bother the stress of a hard-disk failure? Having said that, it's no replacement for backing up your 'important' information. RAID-1 is still susceptible to the dreaded multiple disk failure issue. Having said that, I've been lucky at that hasn't occurred. (Touch wood!)