IDD HDD Block mode
Ben Myers
setting up the hard disk controller (built into the IDE drive) to
transfer multiple sectors into or out of memory before generating a
hardware interrupt that signals the BIOS that a disk operation is
done.
Without this option, the BIOS reads or writes one sector (512 bytes)
at a time, even if a software application program wanted to read or
write more.
The net effect of the IDE HDD block mode option is to reduce the
number of CPU cycles needed to handle the hard disk, freeing these
processor cycles up for apps to use. This improves performance of
multi-tasking environments like Windows NT or 95, Linux and OS/2 quite
a bit. Improves brain-dead mono-tasking DOS only marginally. Same
for Win 3.1 which depends heavily on DOS for all its disk processing.
Best regards,
Ben Myers
KH <fun...@po.pacific.net.sg> wrote:
>What IDE HDD block mode do? Does enabling this option in my bios improve
>performance, my HDD is Seagate 1.2GB st31270.
Zivago 'Jaeman' Lee
> Enabling IDE HDD block mode option in your bios improve performance by
> setting up the hard disk controller (built into the IDE drive) to
> transfer multiple sectors into or out of memory before generating a
> hardware interrupt that signals the BIOS that a disk operation is
> at a time, even if a software application program wanted to read or
> The net effect of the IDE HDD block mode option is to reduce the
> number of CPU cycles needed to handle the hard disk, freeing these
> processor cycles up for apps to use. This improves performance of
> Ben Myers
> KH <fun...@po.pacific.net.sg> wrote:
> >What IDE HDD block mode do? Does enabling this option in my bios improve
> >performance, my HDD is Seagate 1.2GB st31270.
Hi,
Does anybody know why if I turn on Block mode, when transferring files I
get a lot of block errors. Once I turn them off, transferring works fine.
It didn't matter whether I had Smartdrv on or off. Does anybody know why?
If somebody can shed some light on this...
Zivago
Martin Vernon
> What IDE HDD block mode do? Does enabling this option in my bios improve
> performance, my HDD is Seagate 1.2GB st31270.
It allows multiple sectors per interrupt, so if the drive is capable of
16 (some Seagate's do 32) sector mode then it will need only one
interrupt to transfer them, thus reducing interrupt latency (or improving
performance).
--
Martin Vernon, Sysop GB7OS/GB7OSP, Chairman GCPG, IP Co-ordinator N. Wales
GW6HVA@GB7OSP, gw6...@gb7osp.ampr.org, e-mail: mar...@gw6hva.demon.co.uk
Voice: +44 589 900 564 Data: GB7OSP V32.bis, 8N1, ANSI +44 1492 872 467
Duane M. Saylor
> Does anybody know why if I turn on Block mode, when transferring files I
> get a lot of block errors. Once I turn them off, transferring works fine.
> It didn't matter whether I had Smartdrv on or off. Does anybody know why?
> If somebody can shed some light on this...
If you enable block mode, you must re-format the drive to use it. Turning
on block mode on a drive that was not formated with block mode enabled can
cause problems.
Duane
Marnix Timmermans
>> Does anybody know why if I turn on Block mode, when transferring files I
>> get a lot of block errors. Once I turn them off, transferring works fine.
>> It didn't matter whether I had Smartdrv on or off. Does anybody know why?
>> If somebody can shed some light on this...
what do you mean by transferring files? I've never heard of block
errors?
>If you enable block mode, you must re-format the drive to use it. Turning
>on block mode on a drive that was not formated with block mode enabled can
>cause problems.
total BS. Blockmode has to do with the amount of sectors that are
moved per interrupt. Read the EIDE-faq if you want more info
http://thef-nym.sci.kun.nl/~pieterh/storage.html
Marnix
- - - - Marnix Timmermans - - - -
- m.p.h.l.t...@kub.nl -
- http://huizen.dds.nl/~checkhd -
Peter den Haan
"Duane M. Saylor" <dsa...@widomaker.com> wrote:
>If you enable block mode, you must re-format the drive to use it. Turning
>on block mode on a drive that was not formated with block mode enabled can
>cause problems.
Duane, you were thinking of LBA. Block mode has no such problems.
I'd like to add that using excessively large blocks can cause
overrun errors (CRC failures) on the serial ports at high baud
rates.
- Peter
Martin Vernon
Duane M. Saylor (dsa...@widomaker.com) wrote:
> Zivago 'Jaeman' Lee wrote:
>
> > Does anybody know why if I turn on Block mode, when transferring files I
> > get a lot of block errors. Once I turn them off, transferring works fine.
> > It didn't matter whether I had Smartdrv on or off. Does anybody know why?
> > If somebody can shed some light on this...
>
> on block mode on a drive that was not formated with block mode enabled can
> cause problems.
No no, you mean LBA mode. Block mode only selects the ability to transfer
x number of sectors per interrupt, it has absolutely nothing to do with
the logical format of the drive.
Mark Greene
Zivago 'Jaeman' Lee wrote:
>
> On Thu, 27 Jun 1996, Ben Myers wrote:
>
> > Enabling IDE HDD block mode option in your bios improve performance by
> > setting up the hard disk controller (built into the IDE drive) to
> > transfer multiple sectors into or out of memory before generating a
> > hardware interrupt that signals the BIOS that a disk operation is
> > at a time, even if a software application program wanted to read or
> > The net effect of the IDE HDD block mode option is to reduce the
> > number of CPU cycles needed to handle the hard disk, freeing these
> > processor cycles up for apps to use. This improves performance of
> > Ben Myers
> > >What IDE HDD block mode do? Does enabling this option in my bios improve
> > >performance, my HDD is Seagate 1.2GB st31270.
>
> Does anybody know why if I turn on Block mode, when transferring files I
> get a lot of block errors. Once I turn them off, transferring works fine.
> It didn't matter whether I had Smartdrv on or off. Does anybody know why?
> If somebody can shed some light on this...
>
Enabling IDE block mode will indeed improve your disk performance by
transferring multiple blocks per interrupt. One side affect, however,
is that you may end up with comm port errors if the the disk interrupt
routines keeps interrupts disabled for too long (as it handles the
multiple disk blocks) and serial port interrupts aren't serviced.
It would be nice if the BIOS block mode could also specify the number
of blocks to be transferred so we could tune disk transfers so they
don't cause too many comm port errors. I seem to recall that some
software add-on (Disk Rocket?) allows you to set the number of blocks
transferred per interrupt.
Corrections welcome...
-- ._
Mark K. Greene \\/|_\/ If you don't care where
m...@tripos.com _/ you are you can't get lost.
m...@inlink.com
Zivago Lee
>>> Does anybody know why if I turn on Block mode, when transferring files I
>>> get a lot of block errors. Once I turn them off, transferring works fine.
>>> It didn't matter whether I had Smartdrv on or off. Does anybody know why?
>>> If somebody can shed some light on this...
>
>what do you mean by transferring files? I've never heard of block
>errors?
>
>>If you enable block mode, you must re-format the drive to use it. Turning
>>on block mode on a drive that was not formated with block mode enabled can
>>cause problems.
>
>total BS. Blockmode has to do with the amount of sectors that are
>moved per interrupt. Read the EIDE-faq if you want more info
>http://thef-nym.sci.kun.nl/~pieterh/storage.html
When transferring files, I meant when I transfer files with the modem
with any protocol, I get block errors and the modem is always having
to resend them. But, with my new motherboard, this hasn't happened.
Weird. I guess this motherboard has a better interface or something...
Zivago
Zivago Lee
>"Duane M. Saylor" <dsa...@widomaker.com> wrote:
>
> >If you enable block mode, you must re-format the drive to use it. Turning
> >on block mode on a drive that was not formated with block mode enabled can
> >cause problems.
>
>Duane, you were thinking of LBA. Block mode has no such problems.
>
>I'd like to add that using excessively large blocks can cause
>overrun errors (CRC failures) on the serial ports at high baud
>rates.
>
> - Peter
>
>--
>pie...@sci.kun.nl http://thef-nym.sci.kun.nl/~pieterh/
Hi,
That was just what I was getting. Why is that? But, now ever since I
got my new motherboard, its not doing that anymore. It transfers fine
now. I have a Maxtor at PIO Mode 3.
Zivago
Chris Quirke
zl...@scf.usc.edu (Zivago Lee) wrote:
>When transferring files, I meant when I transfer files with the modem
>with any protocol, I get block errors and the modem is always having
>to resend them. But, with my new motherboard, this hasn't happened.
>Weird. I guess this motherboard has a better interface or something...
I think this is a consequence of any off-CPU process that ties up the
bus for too long. Transferring large data blocks from HD, presumably
with interrupts disabled or via DMA, might delay the UART's interrupt
service long enough to allow the buffer to overrun.
Peter den Haan
>>I'd like to add that using excessively large blocks can cause
>>overrun errors (CRC failures) on the serial ports at high baud
>>rates.
zl...@scf.usc.edu (Zivago Lee) writes:
>That was just what I was getting. Why is that?
In MS-DOS and Windows, interrupts are disabled during the actual data
transfer. This means that the serial port will not be serviced. With
larger blocks, the transfer takes more time. Sometimes so much more that
the serial port buffer starts to overflow, at which point you'll get
overruns and CRC errors.
A relatively slow harddisk/interface, high baudrate and excessively
large block size can bring even a 16550 serial port to its knees.
>But, now ever since I got my new motherboard, its not doing that anymore.
Perhaps the data transfer has become faster. Perhaps you went from 16450
to 16550 compatible ports (the latter can buffer more characters before
losing them).
Zivago Lee
On 4 Jul 1996 13:38:53 +0200, pie...@sci.kun.nl (Peter den Haan)
wrote:
>
That's weird. I had 16550 on USR Sportster 28.8 and 16550s onboard
too. I guess my interface is faster. Don't know. Thanks for the info.
Zivago
Videoman
"Duane M. Saylor" <dsa...@widomaker.com> wrote:
>If you enable block mode, you must re-format the drive to use it. Turning
>on block mode on a drive that was not formated with block mode enabled can
>cause problems.
If you mean IDE multi-sector transfer mode, then you are incorrect.
Perhaps you meant Logical Block Addressing, a totally different topic?
\\// \\//\\// -=- Videoman's World - http://www.tiac.net/users/videoman/ -=-
Videoman
Zivago 'Jaeman' Lee <zl...@castor.usc.edu> wrote:
>Does anybody know why if I turn on Block mode, when transferring files I
>get a lot of block errors. Once I turn them off, transferring works fine.
>It didn't matter whether I had Smartdrv on or off. Does anybody know why?
>If somebody can shed some light on this...
Do you mean transferring files over a modem? In that respect, block
errors would be somehow related to the transmission protocol, and have
nothing to do directly with a block mode setting in the CMOS system
setup.
If you mean something else, then please provide more details...
Michael Chan
zl...@scf.usc.edu (Zivago Lee) wrote:
>When transferring files, I meant when I transfer files with the modem
>with any protocol, I get block errors and the modem is always having
>to resend them. But, with my new motherboard, this hasn't happened.
>Weird. I guess this motherboard has a better interface or something...
May be your old motherboard without 16550 UART support serial port.
Bye!
Michael
Zivago Lee
Hi,
I meant over the modem and I was using Zmodem. I have 16550s on my
internal modem and it was on COM2 with no IRQ conflicts. Its really
weird it was doing this.
Zivago
Zivago Lee
Hi,
My modem was an internal with 16550s.
Zivago