[H-GEN] Clock Time Loss When Copying Files

Christopher Biggs chris at stallion.oz.au
Tue Jun 6 22:33:02 EDT 2000

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Martin Pool <mbp at linuxcare.com.au> moved upon the face of the 'Net and spake thusly:

> On Wed, 7 Jun 2000, Frank Brand wrote:
> > 
> > It seems that wheh he does this the clock on the box being copied loses time.
> I wonder if the machine is masking out timer interrupts while doing IO,
> and so losing time.  (Is it a slow machine or hard drive?)  

...or a dumb network card like an NE2000?[1]

If the network card is one that requires Programmed IO transfers, the
time spent at high interrupt priority will be considerable.

Using a NIC with shared memory or DMA support will improve matters

In the interim, using NTP to synchronize clocks will improve matters

(The rest of Martin's suggestions are wise, as usual).


[1] For the uninitiated, the ubiquitous NE2000 (or clones) places a high
    load on the CPU in comparison to other network interface cards.

| Christopher J. Biggs -|- R & D Software Engineer --  Stallion Technologies |
| chris at stallion.oz.au -|- If it isn't broken, I just haven't touched it yet |
\---------veni vidi nuclei deceiri --- I came, I saw, I dumped core----------/

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