Commit Graph

108 Commits

Author SHA1 Message Date
Neel Natu
a09580e7a3 Teach the kernel to recognize that it is executing inside a bhyve virtual
machine.

Obtained from:	NetApp
2013-01-05 19:18:50 +00:00
Andre Oppermann
0060bab556 Prevent long type overflow of realmem calculation on ILP32 by forcing
calculation to be in quad_t space.  Fix style issue with second parameter
to qmin().

Reported by:	alc
Reviewed by:	bde, alc
2012-12-10 12:19:03 +00:00
Andre Oppermann
df905a2bd3 Using a long is the wrong type to represent the realmem and maxmbufmem
variable as they may overflow on i386/PAE and i386 with > 2GB RAM.

Use 64bit quad_t instead.  It has broader kernel infrastructure support
with TUNABLE_QUAD_FETCH() and qmin/qmax() than other available types.

Pointed out by:	alc, bde
2012-11-29 07:30:42 +00:00
Andre Oppermann
ead46972a4 Base the mbuf related limits on the available physical memory or
kernel memory, whichever is lower.  The overall mbuf related memory
limit must be set so that mbufs (and clusters of various sizes)
can't exhaust physical RAM or KVM.

The limit is set to half of the physical RAM or KVM (whichever is
lower) as the baseline.  In any normal scenario we want to leave
at least half of the physmem/kvm for other kernel functions and
userspace to prevent it from swapping too easily.  Via a tunable
kern.maxmbufmem the limit can be upped to at most 3/4 of physmem/kvm.

At the same time divorce maxfiles from maxusers and set maxfiles to
physpages / 8 with a floor based on maxusers.  This way busy servers
can make use of the significantly increased mbuf limits with a much
larger number of open sockets.

Tidy up ordering in init_param2() and check up on some users of
those values calculated here.

Out of the overall mbuf memory limit 2K clusters and 4K (page size)
clusters to get 1/4 each because these are the most heavily used mbuf
sizes.  2K clusters are used for MTU 1500 ethernet inbound packets.
4K clusters are used whenever possible for sends on sockets and thus
outbound packets.  The larger cluster sizes of 9K and 16K are limited
to 1/6 of the overall mbuf memory limit.  When jumbo MTU's are used
these large clusters will end up only on the inbound path.  They are
not used on outbound, there it's still 4K.  Yes, that will stay that
way because otherwise we run into lots of complications in the
stack.  And it really isn't a problem, so don't make a scene.

Normal mbufs (256B) weren't limited at all previously.  This was
problematic as there are certain places in the kernel that on
allocation failure of clusters try to piece together their packet
from smaller mbufs.

The mbuf limit is the number of all other mbuf sizes together plus
some more to allow for standalone mbufs (ACK for example) and to
send off a copy of a cluster.  Unfortunately there isn't a way to
set an overall limit for all mbuf memory together as UMA doesn't
support such a limiting.

NB: Every cluster also has an mbuf associated with it.

Two examples on the revised mbuf sizing limits:

1GB KVM:
 512MB limit for mbufs
 419,430 mbufs
  65,536 2K mbuf clusters
  32,768 4K mbuf clusters
   9,709 9K mbuf clusters
   5,461 16K mbuf clusters

16GB RAM:
 8GB limit for mbufs
 33,554,432 mbufs
  1,048,576 2K mbuf clusters
    524,288 4K mbuf clusters
    155,344 9K mbuf clusters
     87,381 16K mbuf clusters

These defaults should be sufficient for even the most demanding
network loads.

MFC after:	1 month
2012-11-27 21:19:58 +00:00
Alfred Perlstein
79f62ed690 Allow maxusers to scale on machines with large address space.
Some hooks are added to clamp down maxusers and nmbclusters for
small address space systems.

VM_MAX_AUTOTUNE_MAXUSERS - the max maxusers that will be autotuned based on
physical memory.
VM_MAX_AUTOTUNE_NMBCLUSTERS - max nmbclusters based on physical memory.

These are set to the old values on i386 to preserve the clamping that was
being done to all arches.

Another macro VM_AUTOTUNE_NMBCLUSTERS is provided to allow an override
for the calculation on a MD basis.  Currently no arch defines this.

Reviewed by: peter
MFC after: 2 weeks
2012-11-10 02:08:40 +00:00
Alfred Perlstein
7b6d92c0a0 Allow autotune maxusers > 384 on 64 bit machines
A default install on large memory machines with multiple 10gigE interfaces
were not being given enough mbufs to do full bandwidth TCP or NFS traffic.

To keep the value somewhat reasonable, we scale back the number of
maxuers by 1/6 past the 384 point.  This gives us enough mbufs for most
of our pretty basic 10gigE line-speed tests to complete.
2012-10-25 01:46:20 +00:00
Andrey Zonov
ceb0f71506 - Mark some sysctls with CTLFLAG_TUN flag instead of CTLFLAG_RDTUN.
Pointed out by:	avg
Approved by:	kib (mentor)
MFC after:	1 week
2012-09-03 09:26:56 +00:00
Andrey Zonov
c3927cd956 - Make kern.maxtsiz, kern.dfldsiz, kern.maxdsiz, kern.dflssiz, kern.maxssiz
and kern.sgrowsiz sysctls writable.

Approved by:	kib (mentor)
2012-09-02 17:39:02 +00:00
Konstantin Belousov
3fa615bc11 As a safety measure, disable lowering pid_max too much.
Requested by:	Peter Jeremy <peter@rulingia.com>
MFC after:	1 week
2012-08-16 13:04:21 +00:00
Konstantin Belousov
02c6fc2114 Add a sysctl kern.pid_max, which limits the maximum pid the system is
allowed to allocate, and corresponding tunable with the same
name. Note that existing processes with higher pids are left intact.

MFC after:	1 week
2012-08-15 15:56:21 +00:00
Alan Cox
e9a3f7852d Modestly increase the maximum allowed size of the kmem map on i386.
Also, express this new maximum as a fraction of the kernel's address
space size rather than a constant so that increasing KVA_PAGES will
automatically increase this maximum.  As a side-effect of this change,
kern.maxvnodes will automatically increase by a proportional amount.

While I'm here ensure that this change doesn't result in an unintended
increase in maxpipekva on i386.  Calculate maxpipekva based upon the
size of the kernel address space and the amount of physical memory
instead of the size of the kmem map.  The memory backing pipes is not
allocated from the kmem map.  It is allocated from its own submap of
the kernel map.  In short, it has no real connection to the kmem map.
(In fact, the commit messages for the maxpipekva auto-sizing talk
about using the kernel map size, cf. r117325 and r117391, even though
the implementation actually used the kmem map size.)  Although the
calculation is now done differently, the resulting value for
maxpipekva should remain almost the same on i386.  However, on amd64,
the value will be reduced by 2/3.  This is intentional.  The recent
change to VM_KMEM_SIZE_SCALE on amd64 for the benefit of ZFS also had
the unnecessary side-effect of increasing maxpipekva.  This change is
effectively restoring maxpipekva on amd64 to its prior value.

Eliminate init_param3() since it is no longer used.
2011-03-23 16:38:29 +00:00
Sergey Kandaurov
4053b05b91 Make MSGBUF_SIZE kernel option a loader tunable kern.msgbufsize.
Submitted by:	perryh pluto.rain.com (previous version)
Reviewed by:	jhb
Approved by:	kib (mentor)
Tested by:	universe
2011-01-21 10:26:26 +00:00
Christian S.J. Peron
ea235a1449 Add Xen to the list of virtual vendors. In the non PV (HVM) case this fixes
the virtualization detection successfully disabling the clflush instruction.
This fixes insta-panics for XEN hvm users when the hw.clflush_disable
tunable is -1 or 0 (-1 by default).

Discussed with:	jhb
2010-08-06 15:04:40 +00:00
Nathan Whitehorn
bcebf6a165 Reverse the logic of the if statement that sets the default value of
HZ; the list of 1000 Hz platforms was getting unwieldy.

Suggested by:	marcel
2010-06-24 00:27:20 +00:00
Nathan Whitehorn
e864acd42f Move default HZ from 100 to 1000 on powerpc.
Reviewed by:	marcel
MFC after:	2 weeks
2010-06-23 23:26:14 +00:00
Ivan Voras
07ce8d9b43 Document the VM detection type and sysctl a bit better. 2010-03-02 23:57:42 +00:00
Alan Cox
0b993ee5fd When running as a guest operating system, the FreeBSD kernel must assume
that the virtual machine monitor has enabled machine check exceptions.
Unfortunately, on AMD Family 10h processors the machine check hardware
has a bug (Erratum 383) that can result in a false machine check exception
when a superpage promotion occurs.  Thus, I am disabling superpage
promotion when the FreeBSD kernel is running as a guest operating system
on an AMD Family 10h processor.

Reviewed by:	jhb, kib
MFC after:	3 days
2010-02-27 18:00:57 +00:00
Brooks Davis
2e5514defa Don't inforce an upper bound on kern.ngroups. The INT_MAX-1 limit was
too high due to several overflows.  The actual limit is somewhere in the
neighborhood of INT_MAX/4 on 64-bit machines, but most systems could not
support such a limit due to a lack of memory and the cost of duplicate
credentials.

Reported by:	bde
2010-02-24 15:52:18 +00:00
Brooks Davis
412f9500e2 Replace the static NGROUPS=NGROUPS_MAX+1=1024 with a dynamic
kern.ngroups+1.  kern.ngroups can range from NGROUPS_MAX=1023 to
INT_MAX-1.  Given that the Windows group limit is 1024, this range
should be sufficient for most applications.

MFC after:	1 month
2010-01-12 07:49:34 +00:00
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