Hi-cap storage question

Fri Jun 18 17:35:42 PDT 2004

hi ya mark

On Fri, 18 Jun 2004, Mark C. Langston wrote:

> We won't be generating it all at once, but that's our
> short-to-medium-term need.  Right now, today, we're storing/archiving
> a terabyte every 20 days, and getting by with hardware RAID (only
> keeping about 100-200GB live, and rotating the available partitions on a
> FIFO basis) and LTO1 jukeboxes.

so far, its ez enough, since we have 250GB/300GB disks at $150 - $250each
 
- 110vac power and air conditioning and rack space is a separate issue

	- if say each "pc" w/ 4 disks uses 6-8A at 12v
	-> 100W of live current per mb system for about 1TB of storage


	1 PB system would need about 6,000A of +12v power, if it all
	has to stay live at the same time
	( non-trivial at 1 petabyte of storage )

- a blades w/ 4 drives or 1U's with 4 drives would be a major important
  factor in power, space, air conditioning, etc
	- 10 blades per 4U space is trivial to do ( ie 40 drives per 4U )
	-  4 1Us per 4U space ( too small )

	- 10x 4U blades ( 400 disks ) per rack --> fun stuff 
		( each disk is 1A at +12v )

> Right now, the vast bulk of the data is stored in flat files, which does
> not present a problem for us at the moment, neither in terms of access
> (it's write-only during collection), or inode count (the number of files
> is small and finite).  Moving to a database isn't out of the question,
> but if we did, "free" is a very good word.

and hope you have a good "search" algorithm to find the "data" you
need out of the peta/exabyte systems

ibm/oracle has a 15TB db system for $15M :-)
( which is obsurdly priced )

c ya
alvin