Commit Graph

89 Commits

Author SHA1 Message Date
Mike Silbersack
347e22a68b Increase HZ_VM from 10 to 100. While 10 hz saves cpu time
under VM environments, it's too slow for FreeBSD to work
properly.  For example, ping at 10hz pings about every 600ms
instead of about every second.

Approved by:	re (kib)
2009-07-08 01:09:12 +00:00
John Baldwin
9b84ba1cbb Improve the description of a few sysctls.
Submitted by:	bde (partially)
MFC after:	3 days
2009-03-23 20:18:06 +00:00
John Baldwin
42dd14bada Change the sysctls for maxbcache and maxswzone from int to long. I missed
this earlier since these sysctls don't exist in 7.x yet.
2009-03-12 17:23:02 +00:00
John Baldwin
b9f2a7da58 Export the current values of nbuf, ncallout, and nswbuf via read-only
sysctls that match the tunable names.

MFC after:	3 days
2009-03-12 17:21:58 +00:00
John Baldwin
64ecd1399f - Make maxpipekva a signed long rather than an unsigned long as overflow
is more likely to be noticed with signed types.
- Make amountpipekva a long as well to match maxpipekva.

Discussed with:	bde
2009-03-10 21:28:43 +00:00
John Baldwin
5bd65606f4 Adjust some variables (mostly related to the buffer cache) that hold
address space sizes to be longs instead of ints.  Specifically, the follow
values are now longs: runningbufspace, bufspace, maxbufspace,
bufmallocspace, maxbufmallocspace, lobufspace, hibufspace, lorunningspace,
hirunningspace, maxswzone, maxbcache, and maxpipekva.  Previously, a
relatively small number (~ 44000) of buffers set in kern.nbuf would result
in integer overflows resulting either in hangs or bogus values of
hidirtybuffers and lodirtybuffers.  Now one has to overflow a long to see
such problems.  There was a check for a nbuf setting that would cause
overflows in the auto-tuning of nbuf.  I've changed it to always check and
cap nbuf but warn if a user-supplied tunable would cause overflow.

Note that this changes the ABI of several sysctls that are used by things
like top(1), etc., so any MFC would probably require a some gross shims
to allow for that.

MFC after:	1 month
2009-03-09 19:35:20 +00:00
Ivan Voras
98a4431181 Document the relationship between enum VM_GUEST and the vm_guest_sysctl_names
array.

Approved by:	gnn (original version)
2008-12-30 23:49:54 +00:00
Bjoern A. Zeeb
34820bbf06 Hide detect_virtual() along with the accompanying string
arrays under #ifndef XEN to make XEN config compile again.
In case of Xen vm_guest is hard coded.

Move the list for the vm_guest sysctl out of the restictive
bounds as the sysctl is there in either case.
2008-12-27 17:19:16 +00:00
Ivan Voras
3610a2260b By popular request, stringify kern.vm_guest sysctl. Now it returns a
short, self-documenting string describing the detected virtual
environment.

Approved by:	gnn (mentor) (earlier version)
2008-12-18 15:34:38 +00:00
Ivan Voras
3dc309114a Introduce a sysctl kern.vm_guest that reflects what the kernel knows about
it running under a virtual environment. This also introduces a globally
accessible variable vm_guest that can be used where appropriate in the
kernel to inspect this environment.

To make it easier for the long run, an enum VM_GUEST is also introduced,
which could possibly be factored out in a header somewhere (but the
question is where - vm/vm_param.h? sys/param.h?) so it eventually becomes
a part of the standard KPI. In any case, it's a start.

The purpose of all this isn't to absolutely detect that the OS is running
under a virtual environment (cf. "redpill") but to allow the parts of the
kernel and the userland that care about this particular aspect and can do
something useful depending on it to have a standardised interface. Reducing
kern.hz is one example but there are other things that could be done like
avoiding context switches, not using CPU instructions that are known to be
slow in emulation, possibly different strategies in VM (memory) allocation,
CPU scheduling, etc.

It isn't clear if the JAILS/VIMAGE functionality should also be exposed
by this particular mechanism (probably not since they're not "full"
virtual hardware environments). Sometime in the future another sysctl and
a variable could be introduced to reflect if the kernel supports any kind
of virtual hosting (e.g. VMWare VMI, Xen dom0).

Reviewed by:	silence from src-commiters@, virtualization@, kmacy@
Approved by:	gnn (mentor)
Security:	Obscurity doesn't help.
2008-12-17 19:57:12 +00:00
Jung-uk Kim
9bd2cbe43f - Detect Bochs BIOS variants and use HZ_VM as well.
- Free kernel environment variable after its use.
- Fix style(9) nits.
2008-12-08 18:39:59 +00:00
Maxim Sobolev
4da059f304 vm_pnames should be "const char *const[]".
Submitted by:	Christoph Mallon
2008-10-27 08:09:05 +00:00
Maxim Sobolev
fa38c35148 vm_pnames has no reason to be global.
MFC after:	2 weeks
2008-10-27 06:34:41 +00:00
Maxim Sobolev
7f03c419bc Default HZ value (1,000) on i386/amd64 is not very virtual machine friendly.
Due to the nature of the beast it causes lot of unproductive overhead. This
is especially bad when running SMP kernel on VMWare with several virtual
processors - idle FreeBSD guest with SMP kernel takes 150% host CPU time on my
dual-core MacBook Pro when I am enabling two virtual CPUs, making even host
not very usable. Detect when we are running in the sandbox and reduce HZ
to 10 (can be adjusted via VM_HZ in the kernel config) in such cases. This
brings host CPU usage of idle FreeBSD/SMP on two virtual processors down
to 10%.

Detect most popular VM platforms out there - VMWare, Parallels, VirtualBox
and VirtualPC.

MFC after:	2 weeks
2008-10-27 06:25:02 +00:00
Alan Cox
6819e13eeb Correct an error in the comments for init_param3().
Discussed with: silby
2008-07-04 19:36:58 +00:00
Pawel Jakub Dawidek
b109dd74fe - Export HZ value via kern.hz sysctl (this is the same name as for the
loader tunable).
- Document other sysctls in this file and also mark them as loader tunable
  via CTLFLAG_RDTUN flag.

Reviewed by:	roberto
2008-05-09 07:42:02 +00:00
Alfred Perlstein
7c45a9c446 Export maxswzone, maxbcache, maxtsiz, dfldsiz, maxdsiz, dflssiz, maxssiz,
and sgrowsiz via sysctl.

MFC after: 1 week
2007-10-16 10:40:53 +00:00
Kris Kennaway
f098dcded5 Partially revert revision 1.66, which contained a change that did not
correspond to the commit log.  It changed the maxswzone and maxbcache
parameters from int to long, without changing the extern definitions
in <sys/buf.h>.

In fact it's a good thing it did not, because other parts of the system
are not yet ready for this, and on large-memory sparc machines it causes
severe filesystem damage if you try.

The worst effect of the change was that the tunables controlling the
above variables stopped working.  These were necessary to allow such
large sparc64 machines (with >12GB RAM) to boot, since sparc64 did not
set a hard-coded upper limit on these parameters and they ended
up overflowing an int, causing an infinite loop at boot in bufinit().

Reviewed by:	mlaier
2005-10-14 19:15:10 +00:00
Marius Strobl
ea35b592d4 Increase default HZ for sparc64 to 1000. 2005-04-16 15:07:41 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
Bruce M Simpson
4ac33532ef Fix the build. 2004-11-30 03:23:35 +00:00
Peter Wemm
1114f4f9a2 Switch from 1024hz to 1000hz on amd64 to match i386. 1024 is a bad
choice because it is so in sync with stathz (128hz or 4096hz etc).
2004-11-30 00:25:26 +00:00
Dag-Erling Smørgrav
7419d1e25f #include <vm/vm_param.h> instead of <machine/vmparam.h> (the former
includes the latter, but also declares variables which are defined
in kern/subr_param.c).

Change som VM parameters from quad_t to unsigned long.  They refer to
quantities (size limits for text, heap and stack segments) which must
necessarily be smaller than the size of the address space, so long is
adequate on all platforms.

MFC after:	1 week
2004-11-08 18:20:02 +00:00
Marcel Moolenaar
02a20471ab Increase default HZ for ia64 to 1000. 2004-11-08 04:50:02 +00:00
Poul-Henning Kamp
0c7d0f9639 Increase default HZ for i386 to 1000 2004-11-06 11:33:43 +00:00
Warner Losh
7f8a436ff2 Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core
2004-04-05 21:03:37 +00:00
Alan Cox
1dc10fceaa White space and wording changes to init_param3().
Mostly submitted by:	bde
2004-03-30 08:00:11 +00:00
Alan Cox
e3b19536fb Revise the direct or optimized case to use uiomove_fromphys() by the reader
instead of ephemeral mappings using pmap_qenter() by the writer.  The
writer is still, however, responsible for wiring the pages, just not
mapping them.  Consequently, the allocation of KVA for the direct case is
unnecessary.  Remove it and the sysctls limiting it, i.e.,
kern.ipc.maxpipekvawired and kern.ipc.amountpipekvawired.  The number
of temporarily wired pages is still, however, limited by
kern.ipc.maxpipekva.

Note: On platforms lacking a direct virtual-to-physical mapping,
uiomove_fromphys() uses sf_bufs to cache ephemeral mappings.  Thus,
the number of available sf_bufs can influence the performance of pipes
on platforms such i386.  Surprisingly, I saw the greatest gain from this
change on such a machine: lmbench's pipe bandwidth result increased from
~1050MB/s to ~1850MB/s on my 2.4GHz, 400MHz FSB P4 Xeon.
2004-03-27 19:50:23 +00:00
Peter Wemm
8f650450c6 Set default HZ to 1024 for amd64. The comment in kern/tty.c doesn't
apply here because we have 64 bit longs and don't suffer the hz > 169
overflows.
2004-03-14 05:49:31 +00:00
Mike Silbersack
cebde06978 More pipe changes:
From alc:
Move pageable pipe memory to a seperate kernel submap to avoid awkward
vm map interlocking issues.  (Bad explanation provided by me.)

From me:
Rework pipespace accounting code to handle this new layout, and adjust
our default values to account for the fact that we now have a solid
limit on allocations.

Also, remove the "maxpipes" limit, as it no longer has a purpose.
(The limit on kva usage solves the problem of having two many pipes.)
2003-08-11 05:51:51 +00:00
Mike Silbersack
347194c172 Add init_param3() to subr_param. This function is called
immediately after the kernel map has been sized, and is
the optimal place for the autosizing of memory allocations
which occur within the kernel map to occur.

Suggested by:	bde
2003-07-11 00:01:03 +00:00
Mike Silbersack
41f16f8208 Pull in the entire kmem_map size calculation from kern_malloc, rather
than the shortcircuited version I had been using, which only worked
properly on i386 & amd64.

Also, change an autoscale constant to account for the more correct
kmem_map size.

Problem noticed by:     mux
2003-07-08 18:59:21 +00:00
Mike Silbersack
289016f2d1 Put some concrete limits on pipe memory consumption:
- Limit the total number of pipes so that we do not
  exhaust all vm objects in the kernel map.  When
  this limit is reached, a ratelimited message will
  be printed to the console.

- Put a soft limit on the amount of memory consumable
  by pipes.  Once the limit has been reached, all new
  pipes will be limited to 4K in size, rather than the
  default of 16K.

- Put a limit on the number of pages that may be used
  for high speed page flipping in order to reduce the
  amount of wired memory.  Pipe writes that occur
  while this limit is exceeded will fall back to
  non-page flipping mode.

The above values are auto-tuned in subr_param.c and
are scaled to take into account both the size of
physical memory and the size of the kernel map.

These limits help to reduce the "kernel resources exhausted"
panics that could be caused by opening a large
number of pipes.  (Pipes alone are no longer able
to exhaust all resources, but other kernel memory hogs
in league with pipes may still be able to do so.)

PR:			53627
Ideas / comments from:	hsu, tjr, dillon@apollo.backplane.com
MFC after:		1 week
2003-07-08 04:02:31 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Peter Wemm
447b3772dc Change hw.physmem and hw.usermem to unsigned long like they used to be
in the original hardwired sysctl implementation.

The buf size calculator still overflows an integer on machines with large
KVA (eg: ia64) where the number of pages does not fit into an int.  Use
'long' there.

Change Maxmem and physmem and related variables to 'long', mostly for
completeness.  Machines are not likely to overflow 'int' pages in the
near term, but then again, 640K ought to be enough for anybody.  This
comes for free on 32 bit machines, so why not?
2002-08-30 04:04:37 +00:00
Poul-Henning Kamp
e1d970f181 Improve the implementation of adjtime(2).
Apply the change as a continuous slew rather than as a series of
discrete steps and make it possible to adjust arbitraryly huge
amounts of time in either direction.

In practice this is done by hooking into the same once-per-second
loop as the NTP PLL and setting a suitable frequency offset deducting
the amount slewed from the remainder.  If the remaining delta is
larger than 1 second we slew at 5000PPM (5msec/sec), for a delta
less than a second we slew at 500PPM (500usec/sec) and for the last
one second period we will slew at whatever rate (less than 500PPM)
it takes to eliminate the delta entirely.

The old implementation stepped the clock a number of microseconds
every HZ to acheive the same effect, using the same rates of change.

Eliminate the global variables tickadj, tickdelta and timedelta and
their various use and initializations.

This removes the most significant obstacle to running timecounter and
NTP housekeeping from a timeout rather than hardclock.
2002-04-15 12:23:11 +00:00
Mike Silbersack
77a7d074e4 Unconditionally limit maxproc so that it is not possible
to exhaust all kmaps.  The only reward for setting maxproc
to a value which will cause kmap exhaustion is a panic
during a forkbomb attack.

MFC after:	3 days
2002-03-07 04:50:36 +00:00
Matthew Dillon
0b94a0e9f9 Allow the kern.maxusers boot tuneable to be set to 0 (previously only
the kernel config's maxusers could be set to 0 for autosizing to work).
Reviewed by:	rwatson, imp
MFC after:	3 days
2002-02-06 01:19:19 +00:00
Matthew Dillon
4fbd563eb8 Make the 'maxusers 0' auto-sizing code slightly more conservative. Change
from 1 megabyte of ram per user to 2 megabytes of ram per user, and
reduce the cap from 512 to 384.  512 leaves around 240 MB of KVM available
while 384 leaves 270 MB of KVM available.  Available KVM is important
in order to deal with zalloc and kernel malloc area growth.

Reviewed by:	mckusick
MFC: either before 4.5 if re's agree, or after 4.5
2002-01-25 01:54:16 +00:00
Peter Wemm
f6916f666c Proper fix for old config setting maxusers to 8. 2001-12-14 09:39:29 +00:00
Matthew Dillon
7ca592e093 Too many people are compiling kernels with maxusers set to 0 without the new
config.  Hack the kernel to force auto-sizing if the old config is used.
2001-12-14 04:01:08 +00:00
Mike Silbersack
ebacce5e99 Limit maxprocperuid to 9/10 maxproc, and limit maxfilesperproc to 9/10
maxfiles.  This should make local resource exhaustion attacks easier
to handle with a non-tweaked setup.

MFC after:	3 days
2001-12-13 20:00:45 +00:00
Matthew Dillon
66a11b9fb1 Allow maxusers to be specified as 0 in the kernel config, which will
cause the system to auto-size to between 32 and 512 depending on the
amount of memory.

MFC after:	1 week
2001-12-09 01:57:09 +00:00
Matthew Dillon
f286003909 Create a mutex pool API for short term leaf mutexes.
Replace the manual mutex pool in kern_lock.c (lockmgr locks) with the new API.
Replace the mutexes embedded in sxlocks with the new API.
2001-11-13 21:55:13 +00:00
Paul Saab
cbc89bfbfe Make MAXTSIZ, DFLDSIZ, MAXDSIZ, DFLSSIZ, MAXSSIZ, SGROWSIZ loader
tunable.

Reviewed by:	peter
MFC after:	2 weeks
2001-10-10 23:06:54 +00:00
Matthew Dillon
e1616f3a7b Conditionalize VM_SWZONE_SIZE_MAX and VM_BCACHE_SIZE_MAX so MD sections
that don't define these constants don't break.
2001-08-20 16:29:13 +00:00
Matthew Dillon
2f9e4e8025 Limit the amount of KVM reserved for the buffer cache and for swap-meta
information.  The default limits only effect machines with > 1GB of ram
and can be overriden with two new kernel conf variables VM_SWZONE_SIZE_MAX
and VM_BCACHE_SIZE_MAX, or with loader variables kern.maxswzone and
kern.maxbcache.  This has the effect of leaving more KVM available for
sizing NMBCLUSTERS and 'maxusers' and should avoid tripups where a sysad
adds memory to a machine and then sees the kernel panic on boot due to
running out of KVM.

Also change the default swap-meta auto-sizing calculation to allocate half
of what it was previously allocating.  The prior defaults were way too high.
Note that we cannot afford to run out of swap-meta structures so we still
stay somewhat conservative here.
2001-08-20 00:41:12 +00:00
Peter Wemm
ee342e1bf1 Move param.c out of the conf directory and make it fully dynamic.
Tunables are now derived at boot time from maxusers.  ie: change maxusers
via a tunable and all the derivative settings change.  You can change
the other tunables individually as well.  Even hz etc is tunable.
2001-07-26 23:04:03 +00:00
Bosko Milekic
08442f8a82 Introduce numerous SMP friendly changes to the mbuf allocator. Namely,
introduce a modified allocation mechanism for mbufs and mbuf clusters; one
which can scale under SMP and which offers the possibility of resource
reclamation to be implemented in the future. Notable advantages:

 o Reduce contention for SMP by offering per-CPU pools and locks.
 o Better use of data cache due to per-CPU pools.
 o Much less code cache pollution due to excessively large allocation macros.
 o Framework for `grouping' objects from same page together so as to be able
   to possibly free wired-down pages back to the system if they are no longer
   needed by the network stacks.

 Additional things changed with this addition:

  - Moved some mbuf specific declarations and initializations from
    sys/conf/param.c into mbuf-specific code where they belong.
  - m_getclr() has been renamed to m_get_clrd() because the old name is really
    confusing. m_getclr() HAS been preserved though and is defined to the new
    name. No tree sweep has been done "to change the interface," as the old
    name will continue to be supported and is not depracated. The change was
    merely done because m_getclr() sounds too much like "m_get a cluster."
  - TEMPORARILY disabled mbtypes statistics displaying in netstat(1) and
    systat(1) (see TODO below).
  - Fixed systat(1) to display number of "free mbufs" based on new per-CPU
    stat structures.
  - Fixed netstat(1) to display new per-CPU stats based on sysctl-exported
    per-CPU stat structures. All infos are fetched via sysctl.

 TODO (in order of priority):

  - Re-enable mbtypes statistics in both netstat(1) and systat(1) after
    introducing an SMP friendly way to collect the mbtypes stats under the
    already introduced per-CPU locks (i.e. hopefully don't use atomic() - it
    seems too costly for a mere stat update, especially when other locks are
    already present).
  - Optionally have systat(1) display not only "total free mbufs" but also
    "total free mbufs per CPU pool."
  - Fix minor length-fetching issues in netstat(1) related to recently
    re-enabled option to read mbuf stats from a core file.
  - Move reference counters at least for mbuf clusters into an unused portion
    of the cluster itself, to save space and need to allocate a counter.
  - Look into introducing resource freeing possibly from a kproc.

Reviewed by (in parts): jlemon, jake, silby, terry
Tested by: jlemon (Intel & Alpha), mjacob (Intel & Alpha)
Preliminary performance measurements: jlemon (and me, obviously)
URL: http://people.freebsd.org/~bmilekic/mb_alloc/
2001-06-22 06:35:32 +00:00
Poul-Henning Kamp
da936bf80a Remove unneeded <stddef.h> #includes. 2000-10-29 16:57:42 +00:00