Slow rsh performance linux->solaris

[Morgan Fletcher]

I posted previously about slow rdump times from linux to solaris. I
later tried dumping a local partition to another partition on the same
linux box, and it was blazing fast with no errors. So then I just
tried sending packets from linux to (a pipe to rsh to) solaris and
timing it. In this environment, linux is butt-slow when compared to
other unices. All machines are on the same 10base-t network. Check it
out:

  linux->solaris
  time dd if=/dev/zero count=16384 ibs=1k | rsh ale dd of=/dev/null obs=1k
  16384+0 records in
  32768+0 records out
  24459+10016 records in
  16384+0 records out

  real1m27.993s
  user0m0.290s
  sys 0m0.790s

  solaris->solaris (two different boxes):
  time dd if=/dev/zero count=16384 ibs=1k | rsh ale dd of=/dev/null obs=1k
  16384+0 records in
  32768+0 records out
  32768+0 records in
  16384+0 records out

  real0m17.389s
  user0m1.814s
  sys 0m6.696s

  aix->solaris
  # time dd if=/dev/zero count=16384 bs=1k | ( rsh ale 'dd of=/dev/null bs=1k' 
)  
  16384+0 records in.
  16384+0 records out.
  11491+11492 records in
  11491+11492 records out

  real0m15.27s
  user0m0.12s
  sys 0m1.27s

Any ideas as to why rsh/rdump are so slow? If I rcp files from this
linux box to that solaris box it's quite fast, same with ftp. 

morgan
P.S. Would have tried the same thing with hpux, but no /dev/zero.
-- 
V
>> M o r g a n   F l e t c h e r http://www.hahaha.org <<
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Re: Slow rsh performance linux->solaris

[Morgan Fletcher]

George Bonser <[EMAIL PROTECTED]> writes:
> so my guess is that whatever the problem is, it is fixed in a newer
> version of one of the following:
> 
> linux kernel
> netstd package

One thing I forgot to mention is that the machine is running slink &
2.0.36. I was considering an upgrade to potato, and now I'm sure I'll
do it.

I'll double-check the networking issues on Monday, when I'm back in
the office.

Thanks!

morgan
-- 
V
>> M o r g a n   F l e t c h e r http://www.hahaha.org <<
>> Tibi gratias agimus quod nihil fumas. [EMAIL PROTECTED] <<

Re: Slow rsh performance linux->solaris

[Gerhard Kroder]

George Bonser wrote:
 
> I am wondering if there might be some giant delay in resolving the
> hostname (so a .rhosts lookup might work).  A test of this would be ...
> does the total real time stay about the same if you double the transaction
> size.

since installing ssh, i found that simple r* commands go first throug ssh,
and if ssh isn't avaliables on targethost it falls back to r* service.
that's the way it's configured here. maybe you go through ssh too, which
causes that delay? but +1m is quite a lot. *big* key and *slow* machien?

 gerhard