One cause of krb5 test suite slowness on some systems

Ken Raeburn raeburn at MIT.EDU
Fri Jan 30 23:50:49 EST 2009

On Jan 30, 2009, at 23:01, Greg Hudson wrote:
> 1. We start daemons like kadmind and then run "tail -f" on a log  
> file to
> see when they have started.  On most systems, "tail -f" polls its  
> input
> once per second, so that's a one-second delay per system.  You can  
> work
> around this problem on Linux by running "tail -f -s 0.01" instead to
> force faster polling.  This workaround reduced my runtime from 12m to
> 10m on my system, although that's pretty unscientific due to the next
> item.

More portably, for the daemons looking at the [logging] stanza, we  
could tell them to additionally log to stderr, and have expect watch  
for output directly, and do away with the polling.

> None of these issues is trivially fixed in a clean, portable fashion,
> but we have some ideas, and I believe Ken is working on some
> improvements to #3 using t_inetd.

Fixed just now, for some of our tests.  The ones that run as root  
still need tweaking.

With this in place, we can probably also get rid of the code in  
various daemon programs for listening for a connection on a given port  
number, and assume they'll always be run under something inetd-like.


More information about the krbdev mailing list