SATA or SCSI drives - Multiple Read/write speeds.

[Robin Laing]

> hi ya robin/bill On Mon, 8 Dec 2003, Bill Broadley wrote:
> 
SNIP
> 
> definite yupppers one do a benchmark and compare only similar environments
> and apps ... otherwise one is comparing christmas shopping to studing
> to be a vet ( benchmarks not related to each other )
> 

I like the idea of shopping for a christmas vet. :)

> -----
> 
> for which disks ...
> 	- i'd stick with plain ole ide disks
> 	- its cheap
> 	- you can have a whole 2nd system to backup the primary array
> 	for about the same cost as an expensive dual-cpu or scsi-based
> 	system
> 
> for serial ata ...
> 	- dont use its onboard controller for raid ... 
> 	- it probably be as good as onboard raid on existing mb...
> 	( ie ... none of um works right 
> 		works == hands off booting of any disk 
> 		works == data resyncs by itself w/o intervention
> 
> 		but doing the same tests w/ sw raid or hw raid
> 		controller w/ scsi works fine
> 
This is an answer that is at least in the direction of what I am 
looking for.

> 
>>> So I'd look at bonnie++, postmark, or one of the other opensource benchmarks
>>> see if any of those can be configured to be similar to your workload.  If not
>>> write a benchmark that is similar to your workload and post it to the list asking
>>> people to run it on their hardware.  The more effort you put into it the
>>> more responses your likely to get.  Posting a table of performance results
>>> on a website seems to encourage more to participate.
> 
> 
> other benchmark tests you can run ....
> 
> 	http://www.Linux-1U.net/Benchmarks

Correct link,
http://www.Linux-1U.net/BenchMarks

The problem benchmarks software is you need the hardware to test it 
with.  What a nice circle to be involved in.

> 
> other tuning you can to to tweek the last instruction out of the system
> 
> 	http://www.Linux-1U.net/Tuning
>  

I have looked at http://www.Linux-1U.net before posting my questions 
about SATA.

> 
>>> There are no easy answers, it depends on many many variables, the type
>>> of OS, how long the partition has been live (i.e. fragmentation),
>>> the IDE/SCSI chipset, the drivers, the OS, even the cables can have
>>> performance effects.
> 
> 
> (look for the) picture of partitions/layout ... makes  big difference
> 
> 	http://www.Linux-1U.net/Partition/

I would prefer not to use SWAP at all.  Of course 1Gig of ram is now 
minimum I would put into a desktop.

> 
>>> The market seems to be going towards SATA, seems like many if not all major
>>> storage vendors have an entry level SATA product, I've no idea if this
>>> is just the latest fad or justified from a pure price/performance perspective.
> 
> 
> if the disk manufacturers stop making scsi/ide disks .. we wont have
> any choice... unless we go to the super fast "compact flash"
> and its next generation 100GB "compact flash" in the r/d labs 
> which is why ibm sold its klunky mechanical disk drives in favor
> of its new "solid state disks"  ( forgot its official name )
> 

Solid state memory has been talked about for years.  I remember the 
discussion about bubble memory.

> c ya
> alvin
> 
> 

-- 
Robin Laing

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