Commit Graph

17 Commits

Author SHA1 Message Date
Peter Wemm
16e12eab5a Set P_NOLOAD on the pagezero kthread so that it doesn't artificially skew
the loadav.  This is not real load.  If you have a nice process running in
the background, pagezero may sit in the run queue for ages and add one to
the loadav, and thereby affecting other scheduling decisions.
2002-07-19 21:06:01 +00:00
Alan Cox
f23050633f o Remove the acquisition and release of Giant from the idle priority thread
that pre-zeroes free pages.
 o Remove GIANT_REQUIRED from some low-level page queue functions.  (Instead
   assertions on the page queue lock are being added to the higher-level
   functions, like vm_page_wire(), etc.)

In collaboration with:	peter
2002-07-18 17:40:07 +00:00
Alan Cox
072e9cbb50 o Use vm_pageq_remove_nowakeup() and vm_pageq_enqueue() in
vm_page_zero_idle() instead of partially duplicated implementations.
   In particular, this change guarantees that the number of free pages
   in the free queue(s) matches the global free page count when Giant
   is released.

Submitted by:	peter (via his p4 "pmap" branch)
2002-07-16 19:39:40 +00:00
Matthew Dillon
fbcf77c2ea Re-enable the idle page-zeroing code. Remove all IPIs from the idle
page-zeroing code as well as from the general page-zeroing code and use a
lazy tlb page invalidation scheme based on a callback made at the end
of mi_switch.

A number of people came up with this idea at the same time so credit
belongs to Peter, John, and Jake as well.

Two-way SMP buildworld -j 5 tests (second run, after stabilization)
    2282.76 real  2515.17 user  704.22 sys	before peter's IPI commit
    2266.69 real  2467.50 user  633.77 sys	after peter's commit
    2232.80 real  2468.99 user  615.89 sys	after this commit

Reviewed by:	peter, jhb
Approved by:	peter
2002-07-12 20:17:06 +00:00
Peter Wemm
5e13bcd6c4 vm_page_queue_free_mtx is a spin mutex, not a normal sleep mutex.
I do not know why this didn't panic my box, but I have most certainly
been using it:
peter@overcee[3:14pm]~src/sys/i386/i386-110> sysctl -a | grep zero
vm.stats.misc.zero_page_count: 2235
vm.stats.misc.cnt_prezero: 638951
vm.idlezero_enable: 1
vm.idlezero_maxrun: 16

Submitted by:	Tor.Egge@cvsup.no.freebsd.org
Approved by:	Tor's patches are never wrong. :-)
2002-07-08 23:12:37 +00:00
Peter Wemm
b428c5fd23 Turn the zeroidle process off for SMP systems, there is still a possible
TLB problem when bouncing from one cpu to another (the original cpu will
not have purged its TLB if the it simply went idle).

Pointed out by:	 Tor.Egge@cvsup.no.freebsd.org
Approved by:	Tor is never wrong. :-)
2002-07-08 23:09:11 +00:00
Peter Wemm
a58b3a6878 Add a special page zero entry point intended to be called via the single
threaded VM pagezero kthread outside of Giant.  For some platforms, this
is really easy since it can just use the direct mapped region.  For others,
IPI sending is involved or there are other issues, so grab Giant when
needed.

We still have preemption issues to deal with, but Alan Cox has an
interesting suggestion on how to minimize the problem on x86.

Use Luigi's hack for preserving the (lack of) priority.

Turn the idle zeroing back on since it can now actually do something useful
outside of Giant in many cases.
2002-07-08 04:24:26 +00:00
Alan Cox
25524d3eba o Lock accesses to the free queue(s) in vm_page_zero_idle(). 2002-07-07 19:27:57 +00:00
Julian Elischer
e602ba25fd Part 1 of KSE-III
The ability to schedule multiple threads per process
(one one cpu) by making ALL system calls optionally asynchronous.
to come: ia64 and power-pc patches, patches for gdb, test program (in tools)

Reviewed by:	Almost everyone who counts
	(at various times, peter, jhb, matt, alfred, mini, bernd,
	and a cast of thousands)

	NOTE: this is still Beta code, and contains lots of debugging stuff.
	expect slight instability in signals..
2002-06-29 17:26:22 +00:00
Peter Wemm
1a87a0da66 Pass vm_page_t instead of physical addresses to pmap_zero_page[_area]()
and pmap_copy_page().  This gets rid of a couple more physical addresses
in upper layers, with the eventual aim of supporting PAE and dealing with
the physical addressing mostly within pmap.  (We will need either 64 bit
physical addresses or page indexes, possibly both depending on the
circumstances.  Leaving this to pmap itself gives more flexibilitly.)

Reviewed by:	jake
Tested on:	i386, ia64 and (I believe) sparc64. (my alpha was hosed)
2002-04-15 16:00:03 +00:00
Julian Elischer
2c1007663f In a threaded world, differnt priorirites become properties of
different entities.  Make it so.

Reviewed by:	jhb@freebsd.org (john baldwin)
2002-02-11 20:37:54 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00
John Baldwin
29fdb744d1 Process priority is locked by the sched_lock, not the proc lock. 2001-09-01 20:16:30 +00:00
Peter Wemm
3516c025ff Implement idle zeroing of pages. I've been tinkering with this
on and off since John Dyson left his work-in-progress.

It is off by default for now.  sysctl vm.zeroidle_enable=1 to turn it on.

There are some hacks here to deal with the present lack of preemption - we
yield after doing a small number of pages since we wont preempt otherwise.

This is basically Matt's algorithm [with hysteresis] with an idle process
to call it in a similar way it used to be called from the idle loop.

I cleaned up the includes a fair bit here too.
2001-08-25 05:00:44 +00:00
Benno Rice
1f246456a5 The i386-specific includes in this file were "fixed" by bracketing them with
#ifndef __alpha__.  Fix this for the rest of the world by turning it into
#ifdef __i386__.

Reviewed by:	obrien
2001-07-15 04:11:51 +00:00
Matt Jacob
f343cf2135 Apply field bandages to the includes so compiles happen on alpha. 2001-07-05 06:13:44 +00:00
Matthew Dillon
7197571105 Move vm_page_zero_idle() from machine-dependant sections to a
machine-independant source file, vm/vm_zeroidle.c.  It was exactly the
same for all platforms and updating them all was getting annoying.
2001-07-05 01:32:42 +00:00