Though I still don't know specifically how you can tell whether you are in
udma66 mode or not, from all of my research there's no way you should
expect
your 17MB/sec in udma33 to translate to 24MB/sec in udma66. That's a 41%
speed up just from the bus transfer speed, which just isn't going
Given that none of the current drives can sustain rates much greater
than 20MB/s (and most probably hit in the 10-15MB/s range), I don't think
it's surprising that there's no big difference in performance between
burst speeds of 33MB/s and 66MB/s.
For example, IBM's Deskstar 25GP and
But there are some really good things to keep in mind:
- anything 10MB/s sustained is pretty darn good by recent standards.
It wasn't too long ago when you couldn't buy anything that fast,
at least not at PC prices.
- it's easy to predict drive performance over the next few years.
the
But there are some really good things to keep in mind:
- anything 10MB/s sustained is pretty darn good by recent standards.
I personally think so, but many others do not.
It wasn't too long ago when you couldn't buy anything that fast,
at least not at PC prices.
But one must admit
I have done some performance studies at work. As everyone is doing we
are looking at the trend of 9GB - 18GB - 36GB - 72GB - xxxGB driven
by increased demand for data storage. The measured trend is an overall
performance decrease. My guess is that major drive manufacturers will
not be phasing
Jan:
Thanks for the info. But are you using a Promise Ultra66 or and Ultra33?
Does the Promise card pre-boot screen show the card and drives are in UDMA
mode 4? Mine does, but I still do not think it is carrying over to Linux
since if I shut off UDMA66 with the IBM program, put a regular 40
Ski Harrison wrote:
I still get 17MB/sec. I would think I should get
something like you mention below, 23-24MB/sec, double the plain
jane WD 4gig DMA33 drive.
Though I still don't know specifically how you can tell whether you are in
udma66 mode or not, from all of my research there's no way
On Sun, Aug 29, 1999 at 12:37:45AM -0700, Skip Harrison wrote:
Thanks for the info. But are you using a Promise Ultra66 or and Ultra33?
Ultra66
Does the Promise card pre-boot screen show the card and drives are in UDMA
mode 4?
Yes
Mine does, but I still do not think it is carrying over
On Sun, Aug 29, 1999 at 01:07:19AM -0700, Tom Livingston wrote:
Also, Jan mentioned test speeds from both inner cylinders and outer
cylinders. 18MB was the number for inner cylinders, which is very close to
your own number. Does hdparm -tT /dev/hdc test from the inner or outer
cylinders? If
I have been monitoring this mailing list for over a month and have pieced
together as much as I can. Luckily, it also has lots of stuff about UDMA,
which I am trying to implement to run the two drives I want to mirror
(RAID1).
Anyway, I am stymied. I am trying to get UDMA66 out of the Promise
Skip Harrison wrote:
My main drive with all Linux files on it is a WD 4.3g UDMA 33
model. I have
UDMA turned on for this drive (again, a program from WD web site). Using
"hdparm" to check that dma mode is turned on for _both_ drives (turned on
automatically by option in make config), I get
On Sat, Aug 28, 1999 at 05:46:50PM -0700, Skip Harrison wrote:
2. Applied the 2_2_10_uniform-ide-6_20_genam_patch
I've only tried up to the 2.2.10.uniform-ide-6.20.eridanus.patch so far.
Using "hdparm" on the IBM drive, I get 17 MB/sec. Granted, 17 is faster than
13, but is it UDMA 66?
I
My main drive with all Linux files on it is a WD 4.3g UDMA 33 model. I have
UDMA turned on for this drive (again, a program from WD web site). Using
"hdparm" to check that dma mode is turned on for _both_ drives (turned on
automatically by option in make config), I get 12 to 13 MB/sec on
13 matches
Mail list logo
