Pavel Machek <[EMAIL PROTECTED]> writes:
> I tried irlan over 115200 serial line with 2.2.9 linux (virgin). I ran
> ping and scp of big file. Well, after 196K tranfered at 0.5kB/sec (TCP
> essentially stopped working), I gave up. Ping gave values such-as 20
> seconds. Log told me things like "IrLAP, no activity on link". Tcpdump
> showed bursts of packets interleaved by _lots_ of idle time where one
> machine tried to ping another and the other one was just not
> answering.
>
> What is "right" way to transfer data between two computers using IrDA?
> I thought irlan is ok -- but it is not. Performance is simply
> unusable. (zmodem gives 10K/sec over same line).
Well, I don't think you should blame IrLAN since something else is
definitively wrong. I get 10K FTP when using 115200 (and 330K FTP when
using FIR) so I suspect that you have some problems with your serial
driver/config. It might be related to the IrDA stack, but in that case it
has to be something with irtty (or whatever you are using).
One thing which you should do is to set the IrLAN txqueuelen to 0, since
all queueing is done by irtty anyway (this will be fixed in the next
patch). That should fix the problem with high latencies, but there must be
something else that is the main problem, so please post some logs, so we
can find out whats wrong. I would like to see output from ifconfig (or
proc/net/dev). If you can make an output with irdadump, that would be great
(use the -d option!)
PS. I have seen some weird behaviour myself when using 4Mbps which I
suspect has something to do with the the thing that IrLAN has to go thought
a number of BH's before delivering packets (sometimes 3 of them), but I
have not been able to find out whats wrong, and I haven't seen the problem
since 2.1.13x anyway.
-- Dag
--
/ Dag Brattli | The Linux-IrDA Project /
// University of Tromsoe, Norway | Infrared communication for Linux //
/// http://www.cs.uit.no/~dagb | http://www.cs.uit.no/linux-irda/ ///
