Re: [Gnu-arch-users] New feature at the mirror + request for help

[James Blackwell]

On Tue, Mar 23, 2004 at 04:33:19PM +0900, Tez Kamihira wrote:
> On Tue, 23 Mar 2004 02:01:28 -0500, James Blackwell <address@hidden> said:
> >
> > How big is the cache? Is it as bad as having a revision library? back when
> >
> 
> In my box:
> 
ch size[KB]  archive name             archive size  ratio
----------  ------------------------
   23,224   address@hidden   (2.1 megs)   1.5:1
   73,172   address@hidden  (4.5 megs)   15.8:1
   67,632   address@hidden       (15 megs)    4.4:1
   46,540   address@hidden       (22 megs)    2.1:1
  176,028   address@hidden      (48 megs)    3.6:1
  155,624   address@hidden  (102 megs)   1.5:1
----------  ------------------------
 total:  542,220                       193.6      2.7:1

                        (excluding tez.*2004s:  2.4:1 )

So lets assume a ratio of 2.4:1. Right now, 160 archives take 2.1 gigs of
space, or an average of 13.4 megabytes per archive. With about 80
gigabytes of space available (I'm leaving room for the os, user accounts 
and mail to grow), thats room for 6113 total archives. 

We take that 13.4 megs per archive, and add 2.4 times that, and we end up
with 45.56 megs per archive for the cache. That works to room for 1796
total archives.

At this point in time, I'll estimate that I add about 10 archives a week.
I haven't kept track of how many archives a week, but I'm willing to bet
that it's a flattened out quadratric slope. Lets give a hip shot and say
that a year from now I'll be adding 5 archives a day, which works out to
35 archives a week.

Though this isn't correct math (quadratics have a nonlinear slope) we're
off anyways, so why not hip shot some more), lets split the difference
and say that I'll add an average of 22 archives a week. 

In the former case, I'll have 5 years ((6113 - 160 ) / 22 / 52 = 5.2) 
before I either have to buy more drive space 

In the latter case, I'll have only 1.4 years ((1796 - 160 )/22/52 = 1.4)
before I either have to either deny new mirrors or add more drive space

And that's assuming a rather flat parabola. I personally think that at
some point in the near future arch is going to take off like a rocket
ship. In that case, 1.4 years could turn into six months. I don't know if
I'll be able to buy more drive space in six months. Every spare cent I can
afford goes to Tom right now to help him pay the bills.

With all the difficulty I've seen keeping Tom fed, I'm not encouraged
that the arch community is going to come forth and donate the money to buy
three hard drives for a raid 5 when the supermirror starts to run out of
space. 

As such, I'm trying to stick to things that I can do for a really long
time without putting more money into it, in hopes that I can pass enough
time to get more hardware.

The other night, somebody ran a spider on the wiki. The system load jumped
right up to 1.5 and held there for a good while. I'm *already* working on
getting myself into that mental state where I can walk up to the wife six
months from now and say "Honey, I need another server". Who knows. Maybe I
can get another machine for my birthday in August, but more likely I'll
have to get a job somewhere in order to pay for it. :(

-- 
James Blackwell      Using I.T. to bring more             570-407-0488
Owner, Inframix      business to your business     http://inframix.com

GnuPG (ID 06357400) AAE4 8C76 58DA 5902 761D  247A 8A55 DA73 0635 7400