Commit Graph

47 Commits

Author SHA1 Message Date
chs faab7dbb46 count aobj pages (most notably kernel stack pages) as anon pages
for memory usage-balancing purposes.
2002-06-20 15:05:29 +00:00
chs 988df8394c look in the right flags field for PQ_INACTIVE.
make uvmpd_scan_inactive() return void since its return value is ignored.
2002-05-05 16:26:17 +00:00
wiz b36c0a5406 deamon -> daemon 2002-01-21 14:42:26 +00:00
chs ef57a67ca1 fix locking for loaning. in general we should be looking at the page's
uobject and uanon pointers rather than at the PQ_ANON flag to determine
which lock to hold, since PQ_ANON can be clear even when the anon's lock
is the one which we should hold (if the page was loaned from an object
and then freed by the object).
2001-12-31 19:21:36 +00:00
chs 849c9b2bfd add {anon,file,exec}max as a upper bound on the amount of memory that
will be allocated for the respective usage types when there is contention
for memory.

replace "vnode" and "vtext" with "file" and "exec" in uvmexp field names
and sysctl names.
2001-12-09 03:07:19 +00:00
lukem b616d1ca1d add RCSIDs, and in some cases, slightly cleanup #include order 2001-11-10 07:36:59 +00:00
chs 2ed88fe090 several changes prompted by loaning problems:
- fix the loaned case in uvm_pagefree().
 - redo uvmexp.swpgonly accounting to work with page loaning.
   add an assertion before each place we adjust uvmexp.swpgonly.
 - fix uvm_km_pgremove() to always free any swap space associated with
   the range being removed.
 - get rid of UVM_LOAN_WIRED flag.  instead, we just make sure that
   pages loaned to the kernel are never on the page queues.
   this allows us to assert that pages are not loaned and wired
   at the same time.
 - add yet more assertions.
2001-11-06 08:07:49 +00:00
simonb 819bb532e6 Remove some variables that are set but never used. 2001-11-06 06:28:22 +00:00
chs 0c3dfee2f8 skip the swap-out code if there's no swap space configured.
avoid some hangs in low-memory situations.
2001-09-30 02:57:34 +00:00
chs e37c6bf037 move call to pool_drain() outside the pageq lock. 2001-09-26 07:08:41 +00:00
chs 64c6d1d2dc a whole bunch of changes to improve performance and robustness under load:
- remove special treatment of pager_map mappings in pmaps.  this is
   required now, since I've removed the globals that expose the address range.
   pager_map now uses pmap_kenter_pa() instead of pmap_enter(), so there's
   no longer any need to special-case it.
 - eliminate struct uvm_vnode by moving its fields into struct vnode.
 - rewrite the pageout path.  the pager is now responsible for handling the
   high-level requests instead of only getting control after a bunch of work
   has already been done on its behalf.  this will allow us to UBCify LFS,
   which needs tighter control over its pages than other filesystems do.
   writing a page to disk no longer requires making it read-only, which
   allows us to write wired pages without causing all kinds of havoc.
 - use a new PG_PAGEOUT flag to indicate that a page should be freed
   on behalf of the pagedaemon when it's unlocked.  this flag is very similar
   to PG_RELEASED, but unlike PG_RELEASED, PG_PAGEOUT can be cleared if the
   pageout fails due to eg. an indirect-block buffer being locked.
   this allows us to remove the "version" field from struct vm_page,
   and together with shrinking "loan_count" from 32 bits to 16,
   struct vm_page is now 4 bytes smaller.
 - no longer use PG_RELEASED for swap-backed pages.  if the page is busy
   because it's being paged out, we can't release the swap slot to be
   reallocated until that write is complete, but unlike with vnodes we
   don't keep a count of in-progress writes so there's no good way to
   know when the write is done.  instead, when we need to free a busy
   swap-backed page, just sleep until we can get it busy ourselves.
 - implement a fast-path for extending writes which allows us to avoid
   zeroing new pages.  this substantially reduces cpu usage.
 - encapsulate the data used by the genfs code in a struct genfs_node,
   which must be the first element of the filesystem-specific vnode data
   for filesystems which use genfs_{get,put}pages().
 - eliminate many of the UVM pagerops, since they aren't needed anymore
   now that the pager "put" operation is a higher-level operation.
 - enhance the genfs code to allow NFS to use the genfs_{get,put}pages
   instead of a modified copy.
 - clean up struct vnode by removing all the fields that used to be used by
   the vfs_cluster.c code (which we don't use anymore with UBC).
 - remove kmem_object and mb_object since they were useless.
   instead of allocating pages to these objects, we now just allocate
   pages with no object.  such pages are mapped in the kernel until they
   are freed, so we can use the mapping to find the page to free it.
   this allows us to remove splvm() protection in several places.

The sum of all these changes improves write throughput on my
decstation 5000/200 to within 1% of the rate of NetBSD 1.5
and reduces the elapsed time for "make release" of a NetBSD 1.5
source tree on my 128MB pc to 10% less than a 1.5 kernel took.
2001-09-15 20:36:31 +00:00
thorpej 9917ae5683 G/c a comment that no longer applies. 2001-06-27 18:52:10 +00:00
chs 2d06d7932a don't for memory in uao_set_swlot() since we're holding spinlocks,
instead return -1.  adjust callers to handle this new error return.
fixes PR 13194.
2001-06-23 20:52:03 +00:00
chs 3845302904 remove trailing whitespace. 2001-05-25 04:06:11 +00:00
ross 892627dd05 Merge the swap-backed and object-backed inactive lists. 2001-05-22 00:44:44 +00:00
thorpej 0b8c6fcc77 Fix a silly mistake I made when reworking the uvm inactive list
some time ago.  The mistake was to check that the page was not
referenced since the last active scan before moving it to inactive.
Now we just clear reference and move it to inacive (which is where
the second clock hand sweep occurs).
2001-05-07 22:01:28 +00:00
chs dd82ad8e2c eliminate the VM_PAGER_* error codes in favor of the traditional E* codes.
the mapping is:

VM_PAGER_OK		        0
VM_PAGER_BAD		        <unused>
VM_PAGER_FAIL		        <unused>
VM_PAGER_PEND		        0 (see below)
VM_PAGER_ERROR		        EIO
VM_PAGER_AGAIN		        EAGAIN
VM_PAGER_UNLOCK		        EBUSY
VM_PAGER_REFAULT	        ERESTART

for async i/o requests, it used to be possible for the request to
be convert to sync, and the pager would return VM_PAGER_OK or VM_PAGER_PEND
to indicate whether the caller should perform post-i/o cleanup.
this is no longer allowed; pagers must now return 0 to indicate that
the async i/o was successfully started, and the caller never needs to
worry about doing the post-i/o cleanup.
2001-03-10 22:46:45 +00:00
chs 83d071a318 add UBC memory-usage balancing. we track the number of pages in use for
each of the basic types (anonymous data, executable image, cached files)
and prevent the pagedaemon from reusing a given page if that would reduce
the count of that type of page below a sysctl-setable minimum threshold.
the thresholds are controlled via three new sysctl tunables:
vm.anonmin, vm.vnodemin, and vm.vtextmin.  these tunables are the
percentages of pageable memory reserved for each usage, and we do not allow
the sum of the minimums to be more than 95% so that there's always some
memory that can be reused.
2001-03-09 01:02:10 +00:00
thorpej 1779f8f71b Page scanner improvements, behavior is actually a bit more like
Mach VM's now.  Specific changes:
- Pages now need not have all of their mappings removed before being
  put on the inactive list.  They only need to have the "referenced"
  attribute cleared.  This makes putting pages onto the inactive list
  much more efficient.  In order to eliminate redundant clearings of
  "refrenced", callers of uvm_pagedeactivate() must now do this
  themselves.
- When checking the "modified" attribute for a page (for clearing
  PG_CLEAN), make sure to only do it if PG_CLEAN is currently set on
  the page (saves a potentially expensive pmap operation).
- When scanning the inactive list, if a page is referenced, reactivate
  it (this part was actually added in uvm_pdaemon.c,v 1.27).  This
  now works properly now that pages on the inactive list are allowed to
  have mappings.
- When scanning the inactive list and considering a page for freeing,
  remove all mappings, and then check the "modified" attribute if the
  page is marked PG_CLEAN.
- When scanning the active list, if the page was referenced since its
  last sweep by the scanner, don't deactivate it.  (This part was
  actually added in uvm_pdaemon.c,v 1.28.)

These changes greatly improve interactive performance during
moderate to high memory and I/O load.
2001-01-28 23:30:42 +00:00
thorpej 37247109d1 When considering a page for deactivation, check to see if the
page has been referenced since the last time it was considered.
If it was, don't deactivate the page.
2001-01-25 00:24:48 +00:00
mycroft 91a4c18e32 Put back the pmap_is_referenced() check from the original UVM code in the
inactive list scans.  Without this, the referenced bit was essentially ignored.
2001-01-25 00:10:03 +00:00
chs cf25b3fa04 continue processing the inactive queue past the free target when
we're enforcing the limit on the number of vnode pages.
2000-12-13 17:03:32 +00:00
simonb 33999a4224 Move uvm_pgcnt_vnode and uvm_pgcnt_anon into uvmexp (as vnodepages and
anonpages), and add vtextpages which is currently unused but will be
used to trace the number of pages used by vtext vnodes.
2000-11-30 11:04:43 +00:00
chs aeda8d3b77 Initial integration of the Unified Buffer Cache project. 2000-11-27 08:39:39 +00:00
bjh21 3e6dc8178c Ensure that uvmexp.freemin is above the kernel reserved-page count.
When it wasn't (which could happen on a 4Mb machine with 32kb pages),
uvm_pagealloc_strat could refuse to allocate user memory, while the pagedaemon
didn't think it was worth freeing any more, resulting in the system seizing up.
2000-08-20 10:24:14 +00:00
thorpej a91e7a7c6d Don't bother with a trampoline to start the pagedaemon and
reaper threads.
2000-08-12 22:41:53 +00:00
mrg dea44a9ec4 remove include of <vm/vm.h> 2000-06-27 17:29:17 +00:00
mrg 2f159a1bac remove/move more mach vm header files:
<vm/pglist.h> -> <uvm/uvm_pglist.h>
	<vm/vm_inherit.h> -> <uvm/uvm_inherit.h>
	<vm/vm_kern.h> -> into <uvm/uvm_extern.h>
	<vm/vm_object.h> -> nothing
	<vm/vm_pager.h> -> into <uvm/uvm_pager.h>

also includes a bunch of <vm/vm_page.h> include removals (due to redudancy
with <vm/vm.h>), and a scattering of other similar headers.
2000-06-26 14:20:25 +00:00
thorpej 8e930a51fe Const poison uvm_wait(). 1999-11-04 21:51:42 +00:00
chs f3a668ed84 eliminate the PMAP_NEW option by making it required for all ports.
ports which previously had no support for PMAP_NEW now implement
the pmap_k* interfaces as wrappers around the non-k versions.
1999-09-12 01:16:55 +00:00
thorpej 3f176180d5 Garbage collect thread_sleep()/thread_wakeup() left over from the old
Mach VM code.  Also nuke iprintf(), which was no longer used anywhere.

Add proclist locking where appropriate.
1999-07-22 22:58:38 +00:00
thorpej 6eb9ee7cd8 - Change uvm_{lock,unlock}_fpageq() to return/take the previous interrupt
level directly, instead of making the caller wrap the calls in
  splimp()/splx().
- Add a comment documenting that interrupts that cause memory allocation
  must be blocked while the free page queue is locked.

Since interrupts must be blocked while this lock is asserted, tying them
together like this helps to prevent mistakes.
1999-05-24 19:10:57 +00:00
mycroft 99b341de15 Adjust a comparison so that the pagedaemon doesn't get stuck ping-ponging with
a process trying to allocate memory.
1999-03-30 10:12:01 +00:00
chs 92045bbba9 add uvmexp.swpgonly and use it to detect out-of-swap conditions.
numerous pagedaemon improvements were needed to make this useful:
 - don't bother waking up procs waiting for memory if there's none to be had.
 - start 4 times as many pageouts as we need free pages.
   this should reduce latency in low-memory situations.
 - in inactive scanning, if we find dirty swap-backed pages when swap space
   is full of non-resident pages, reactivate some number of these to flush
   less active pages to the inactive queue so we can consider paging them out.
   this replaces the previous scheme of inactivating pages beyond the
   inactive target when we failed to free anything during inactive scanning.
 - during both active and inactive scanning, free any swap resources from
   dirty swap-backed pages if swap space is full.  this allows other pages
   be paged out into that swap space.
1999-03-26 17:33:30 +00:00
mrg a0139bc39d remove now >1 year old pre-release message. 1999-03-25 18:48:49 +00:00
chs e4c4ea06b4 remove outdated comment. 1998-11-04 07:06:05 +00:00
chs 549cd579e5 shift by PAGE_SHIFT instead of multiplying or dividing by PAGE_SIZE. 1998-10-18 23:49:59 +00:00
eeh a2dd74ed79 Merge paddr_t changes into the main branch. 1998-08-13 02:10:37 +00:00
pk 20f05a4bb5 Include pool_drain() in page scans. 1998-07-23 20:36:09 +00:00
mrg 8106d13596 KNF. 1998-03-09 00:58:55 +00:00
mrg d90485202c - add defopt's for UVM, UVMHIST and PMAP_NEW.
- remove unnecessary UVMHIST_DECL's.
1998-02-10 14:08:44 +00:00
mrg 7d3aef40b3 keep statistics on pageout/pagein, total pages, and total operations. 1998-02-09 13:08:22 +00:00
mrg 0a058cb62f implement counters for pages paged in/out 1998-02-07 17:00:36 +00:00
mrg 1f6b921cf7 restore rcsids 1998-02-07 11:07:38 +00:00
chs 9b371040ea keep track of how many pages are currently being paged out,
stop initiating new pageouts when "(free + paging) > freetarg".
fix pageq locking.
1998-02-07 02:35:11 +00:00
thorpej 9eb328b495 RCS ID police. 1998-02-06 22:26:13 +00:00
mrg f2caacc717 initial import of the new virtual memory system, UVM, into -current.
UVM was written by chuck cranor <chuck@maria.wustl.edu>, with some
minor portions derived from the old Mach code.  i provided some help
getting swap and paging working, and other bug fixes/ideas.  chuck
silvers <chuq@chuq.com> also provided some other fixes.

this is the UVM kernel code portion.


this will be KNF'd shortly.  :-)
1998-02-05 06:25:08 +00:00