Re: Re: VACUUM and 24/7 database operation

I remember the days way back when America Online (that's AOL to you
youngsters) ran under GEOWORKS and had just come out for Windows 3.1.  We
used to pay for every minute we were online over a certain number of hours.
 There were different pricing packages, but I always took the one that made
the individual minutes the least expensive, and that was 6 cents per minute.

Even way back then when every minute cost AOL tons and tons and tons of
money, they would go down about once every two weeks for either three,
four, or five hours for maintenance.  I remember it quite well.  A message
would come on the screen at either 2am, 3am, or 4am (it varied from time to
time) saying that they were going down until 7am.  It was always until 7am
(that was the only thing that was predictable about every instance).

They were stupid for doing business that way.  They probably lost
customers.  Maybe even 20 a week.

But wait.  Even though they operated that way, AOL is now a formidable
media and communications powerhouse.

The lesson is that you gotta to do what you gotta to do.  Even those with
the word "Online" right in their name would go offline every so often,
regardless of their destiny to become a formidable media and communications
powerhouse.

If you have to vacuum for 2 minutes a day, then vacuum for 2 minutes a day.
 When you're a formidable media and communications powerhouse, then you can
hire someone to program PostgreSQL to do what you want it to do.  Of
course, if you're a formidable media and communications powerhouse, you'll
probably switch to Oracle and make LE richer instead of giving some poor
sap a job, but that's business, too.

Doug

At 05:13 PM 1/23/01 -0800, Tiger Technologies wrote:
>At 1/23/01 4:20 PM, Alfred Perlstein wrote:
>
>>* Steve Wolfe <steve@iboats.com> [010123 13:11] wrote:
>>>   Well, here's what it comes down to:  Do you want updates to happen
>>> quickly, and vacuum when load is low, or do you want updates to be slow
all
>>> the time?  I suppose that there are some sites that can't find two minutes
>>> per day when updates will block (not selects), but I imagine they're very
>>> few.
>>
>>There are some sites where going for more than an hour without a
>>VACUUM makes response times unnaceptable, and each vacuum can take
>>20 minutes a run.
>
>
>In addition, the suggestion that vacuum isn't a problem because it only
>takes two minutes is misleading.
>
>Sure, it's only 2 minutes out of 24 hours. However, any given visitor
>isn't at my site for 24 hours. If she arrives just as I'm starting the
>vacuum, and it takes her less than two minutes to give up and go
>somewhere else, the site was unavailable 100% of the time as far as she's
>concerned.
>
>If your site is down two minutes a day, and you have 14,000 unique
>visitors a week, each of whom requires a database update, that's 20
>people a week for whom the site isn't working when they arrive.
>
>--
>Robert L Mathews, Tiger Technologies