We help IT Professionals succeed at work.

Synchronous Data transfer!

hirbyfam
hirbyfam asked
on
Medium Priority
225 Views
Last Modified: 2010-04-12
I'm gonna buy a UW scsi drive soon...
can someone explain when you attain synchronous data
   transfer
can the 40 MB/s rates only be attained while copying to mem?
also...is it safe to enable write caching?

thanks
Chris
Comment
Watch Question

Commented:
40MB/S is an THEORETICAL value. i got a IBM DORS 2.1GB UWSCSI/3 drive, running with a AHAH2940UW controller.. and it gives about 4-6MB/sec.. 40MB/sec is the rate data is shuffled from the disks to the onboard cache ram on the disk. Write caching is safe if you can guarantee that the system wont fail (power failure etc etc)

Not the solution you were looking for? Getting a personalized solution is easy.

Ask the Experts

Author

Commented:
ah yes the DORS - Ultrastar ES
I'm gonna get the Ultrastar 2ES 4.3 I think - DCAS
and use a Tekram DC390F controller

thanks for answering

Chris
j2

Commented:
still... dont expect anywhere NEAR 40MB/sec, 40MB/sec is the theoretical max speed of the UWSCSI bus

Author

Commented:
well yeah...
I'm interested in media streaming speeds, and sustained
   rates
I think zdnet needs to do an ultraSCSI drive test comparing
   sustained rates, even between different partitions
cuz that is mainly what I'm interested in...

cyas
j2

Commented:
well, then the Ultrastar is a good choice.. altough the Cheetah II vaporizes it.

Author

Commented:
what about the Ultrastar 9ZX!
10,020 rpm
6.3 ms seek
17.x meg/sec minimum sustained
!!!!!!!
j2

Commented:
havent seen any benchmarks from an independant source yet.. but it is clearly intended as a "Cheetah killler"
Access more of Experts Exchange with a free account
Thanks for using Experts Exchange.

Create a free account to continue.

Limited access with a free account allows you to:

  • View three pieces of content (articles, solutions, posts, and videos)
  • Ask the experts questions (counted toward content limit)
  • Customize your dashboard and profile

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

OR

Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.