This fixes some nasty procfs problems for SMP, makes ps(1) run much faster,
and makes ps(1) even less dependent on /proc which will aid chroot and
jails alike.
To disable this facility and revert to previous behaviour:
sysctl -w kern.ps_arg_cache_limit=0
For full details see the current@FreeBSD.org mail-archives.
and CPU runtime because it can't access the user area via /proc/<pid>/mem.
This is because the uarea is not mapped into the process address space
at USRSTACK on the alpha like it is on the x86.
Since I'm haven't been able to wrap my brain around the VM system enough
to be able to figure out how to achieve this mapping, and since it's
questionable that such an architectural change is correct, I implemented
a workaround to allow ps(1) to read the uarea from /dev/kmem using
kvm_read() instead of from the process address space via kvm_uread().
The kludge is hidden inside #ifdef __alpha__/#endif so as not to impact
the x86. (Note that top(1) probably uses this same gimmick since it works
on FreeBSD/alpha.)
Reviewed by: dfr
Use /dev/null for opening the kvm library, we don't need access to /dev/mem
anymore.
ps can now run without the setgid(kmem) bit. If it does it will not be
able to show argv/envp for another uid's processes unless you are root.
for users who are root, or in group wheel. This is useful on large timesharing
systems where a PS command can cause the system to grind to a halt. The
ability to get the information isn't diminished for those who really need the
additional detail (administrators.) Normal users won't see any difference unless
the processes are swapped out. The "really get it mode" is invoked by the
use of an additional flag in the command string "-f". New/old behavior is
selectable with a compile option.
PR: 5196
Submitted by: Matt Dillon <dillon@best.net>
VM structure (eg: credentials etc) and it's highly unlikely we'll ever
get to see the "tainted" BSD<=4.3 VM code in public use. Although it
indicated the way some things used to be done, it obfuscates things too
much.
appears, not the longest _maximum_ username (this should probably also go
into 2.2, for the day when we bump up the username length there too).
Submitted-By: Terry Lambert <terry@lambert.org>
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
the full argument vector.
I've bumped into a few things that expected this switch to be present,
the most recent was the snmp package in ports. I'm not 100% sure of the
origins of this, but Linux has it, so does the "BSD-compatable" version
of ps on our SVR4 systems (so I assume SunOS has it too).
list the processes belonging to a particular user without having to use
`-u' and grepping for the username. Basically you can now get a short
`ps -x' like list (with more space for the command) for other users.
/usr/src/bin. Note that some patches are still needed in that directory.
I (Joerg) finished most of Philippe's cleanup. /bin/sh will still
need *allot* of work, however.
Submitted by: charnier@lirmm.fr (Philippe Charnier)
