Re: maxlwp

[christos%zoulas.com@localhost (Christos Zoulas)]

On Mar 29,  2:18pm, yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi) wrote:
-- Subject: maxlwp

| hi,
| 
| i have some questions about maxlwp stuff.
| 
| - unlike kern.maxproc which restricts the total number of processes in
| a system, kern.maxlwp's sole purpose is to restrict setrlimit. is it right?
| if so, why the usual kauth check to prevent raising a hard limit is not
| enough?

It should be enough.
 
| - default cpu_maxlwp() returns 2048.  what's the rationale of this
| small value?  IMO a better default is "unlimited".

I am not sure what a reasonable value for this is. It was the number that
came out of my hat at the time.

| - i want login.conf support for this.  is the attached patch ok?

LGTM.

christos
| 
| YAMAMOTO Takashi
| 
| --Boundary-20130329230857-1693902
| Content-Type: Text/Plain; charset=us-ascii
| Content-Disposition: attachment; filename="a.diff"
| 
| Index: lib/libutil/login_cap.c
| ===================================================================
| RCS file: /cvsroot/src/lib/libutil/login_cap.c,v
| retrieving revision 1.30
| diff -u -p -r1.30 login_cap.c
| --- lib/libutil/login_cap.c   7 Apr 2012 16:16:34 -0000       1.30
| +++ lib/libutil/login_cap.c   29 Mar 2013 14:09:51 -0000
| @@ -420,6 +420,7 @@ static struct {
|       { RLIMIT_RSS,           R_CSIZE, "memoryuse", },
|       { RLIMIT_MEMLOCK,       R_CSIZE, "memorylocked", },
|       { RLIMIT_NPROC,         R_CNUMB, "maxproc", },
| +     { RLIMIT_NTHR,          R_CNUMB, "maxthread", },
|       { RLIMIT_NOFILE,        R_CNUMB, "openfiles", },
|       { RLIMIT_CORE,          R_CSIZE, "coredumpsize", },
|       { RLIMIT_SBSIZE,        R_CSIZE, "sbsize", },
| Index: share/man/man5/login.conf.5
| ===================================================================
| RCS file: /cvsroot/src/share/man/man5/login.conf.5,v
| retrieving revision 1.26
| diff -u -p -r1.26 login.conf.5
| --- share/man/man5/login.conf.5       30 Apr 2012 11:07:28 -0000      1.26
| +++ share/man/man5/login.conf.5       29 Mar 2013 14:09:52 -0000
| @@ -167,6 +167,11 @@ Number of login attempts after which to 
|  Maximum number of processes.
|  .\"
|  .sp
| +.It Sy maxthread Ta number Ta "" Ta
| +Maximum number of threads.
| +First thread of each process are not counted against this.
| +.\"
| +.sp
|  .It Sy memorylocked Ta size Ta "" Ta
|  Maximum locked in core memory size limit.
|  .\"
| 
| --Boundary-20130329230857-1693902--
-- End of excerpt from YAMAMOTO Takashi