[issue1137] Process stuck with an empty STATE

[YONETANI Tomokazu]

On Tue, Jan 20, 2009 at 08:00:04PM +0000, Simon 'corecode' Schubert (via DragonFly issue tracker) wrote:
> 
> Simon 'corecode' Schubert <corecode at fs.ei.tum.de> added the comment:
> 
> does this still happen?

Yes, it's happening now.  My mail server is running a UP kernel built from
941f5de0 (around Oct. 10), but I can't find a relavant fix on
DragonFly_RELEASE_2_0 branch.  I have another box running -DEVELOPMENT,
but its uptime is probably not long enough to reproduce it.

$ top -n -U qhwt 4
load averages:  0.00,  0.00,  0.00  up 100+00:41:22    11:01:26
78 processes:  78 running

Mem: 116M Active, 210M Inact, 138M Wired, 16M Cache, 59M Buf, 1220K Free
Swap: 2048M Total, 15M Used, 2033M Free


  PID USERNAME  PRI NICE  SIZE    RES STATE    TIME   WCPU    CPU COMMAND
63039 qhwt      179   0  2084K  1136K RUN      0:00 1161.00% 56.69% top
18535 qhwt      159   0     0K     4K          0:00  0.00%  3.91% git
18527 qhwt      159   0     0K     4K          0:00  0.00%  3.91% git
18517 qhwt      157   0     0K     4K          0:00  0.00%  1.95% git

I played with kgdb a bit and found that these 3 processes are on zombproc
but with p_stat==SACTIVE and p_lock==1.  I have no idea how it happened.