sendfile problem (Re: Network related procs hang in unusual sfpbsy state)

[Andrew Gallatin]

Gary Stanley writes:
 > New current kernel from about 3 days ago, certain processes hang after 
 > about a day in this state;
 > 
 >     80   599     1   0 -16 -2 59020 53548 sfpbsy D<    ??  1141:08.65 
 > /mnt/zeus/web/bin/zeus.web

This means that the webserver was trying to send a file via
sendfile(), it encountered a busy page, and went to sleep waiting for
that page to be not-busy.  But nothing ever woke it up...

You might be able to work around this temporarily by disabling
sendfile on your web server.  But its something which needs to be
fixed.

It would be interesting to look at the page in question to see if its
still busy.  Do you have a gdb which can do kernel debugging?
(apparently ports/dev/gdb53 can..)

Drew