Re: Ethernet Slowdown Every 20 sec

Maybe the driver is missing an interrupt and thereby using up a buffer,
either on-chip or in memory. Periodically, NDIS calls the driver and asks
it "Are you locked up?". The driver might be checking for lost buffers
there and deciding that, yes, it is locked up, which results in a driver
reset, which might slow things down for a few seconds like that.

Paul T.

"Murray Simpson" <MurraySimpson@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:E52C05A3-2DF2-4871-958A-4C1587F34D4D@xxxxxxxxxxxxxxxx
Thanks for the quick reply. I didn't add one, so I guess it must be a
driver
problem of some sort. :-(

"Paul G. Tobey [eMVP]" wrote:

Probably some problem with the driver for the wired Ethernet card. No,
there's no background process that runs that frequently, unless you added
one.

Paul T.

"Murray Simpson" <MurraySimpson@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message
news:E57737D4-96D6-4AED-874D-BDC4093E2759@xxxxxxxxxxxxxxxx
I am using a Windows CE 5.0 device to send Ethernet data by UDP to a PC.
The
data gets received properly, but every 20 seconds there is a
significant
stoppage of throughput in which no data gets sent for a second or two.
Curiously I only have this problem when sending data over a wired
Ethernet
connection (DM9CE1) ... when I subsitute the device's built-in wireless
Ethernet connection instead, everything works perfectly. Also, the 20
second
interval seems to be independent of how much data is sent, so I don't
think
it's related to a buffer problem. The amount of data being sent is not
particularly huge (approx. 10KBytes / sec).

I was wondering if there might be some sort of CE 5.0 process running
in
the
background that could tie up the wired Ethernet port every 20 seconds?

Obviously I'd like to get rid of this pause in UDP throughput... our
app
is
meant to be real-time so a pause of a second or two every 20 seconds is
too
much!





.

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