the unmapped page.
* This is needed by everyone who calls this to make sure modifications to a
page aren't ignored. Namely, the page scanner and the page thief were
affected.
* Cleaned up locking the page's cache a bit in page_thief(); there is now
a helper class that takes care of everything.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22438 a95241bf-73f2-0310-859d-f6bbb57e9c96
* We now have a page writer that takes some pages from the modified queue
and writes it back every few seconds. It can be triggered by the page
scanner to do that more often, though. That mechanism can be greatly
improved once we have our I/O scheduler working.
* Removed vm_page_write_modified_page() again - it was all "eaten up" by
the page writer.
* Reworked vm_page_write_modified_pages() a bit: it now uses
vm_test_map_modification() and vm_clear_map_flags() instead of the
iterating over all areas which wouldn't even work correctly.
The code is much simpler now, too.
* You usually put something to the tail of a queue, and remove the contents
from the head, not vice versa - changed queue implementation to reflect this.
* Additionally, there is now a enqueue_page_to_head() if you actually want the
opposite.
* vm_page_requeue() allows you to move a page in a queue to the head or tail.
* Replaced vm_clear_map_activation() with vm_clear_map_flags() which allows
you to clear other flags than PAGE_ACCESSED.
* The page scanner dumps now some arguments with each run.
* Removed the old disabled pageout_daemon() from NewOS.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22348 a95241bf-73f2-0310-859d-f6bbb57e9c96
* The page daemon now runs independently from the low memory state.
* It now also increases its frequency and scanned pages, as well as decreases
the interval between runs with increasing memory pressure.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22314 a95241bf-73f2-0310-859d-f6bbb57e9c96
a reference to a by them not yet referenced cache was not correct.
They only incremented the reference count, but a vnode cache reference
includes also a vnode reference. In case of the page daemon this would
cause vnode references to be lost (causing bug #1465).
* The page daemon used an unsafe method to access a yet unreferenced
page cache. There was nothing that prevented the cache from being
deleted while the page daemon tried to get a reference. The
vm_page::cache field is now protected by the page cache table
spinlock, too, which the new function
vm_cache_acquire_page_cache_ref(), used by the page daemon, also
acquires while trying to get the reference.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22208 a95241bf-73f2-0310-859d-f6bbb57e9c96
* The vm_translation_map is now correctly held in all of the vm_ mapping
functions.
* Removed the old vm_daemons.c file - there is now a new vm_daemons.cpp
which contains the beginnings of our new page daemon.
So far, it's pretty static and not much tested. What it currently does
is to rescan all pages in the system with a two-handed clock algorithm
and push pages into the modified and inactive lists.
* These inactive pages aren't really stolen yet, even though their mappings
are removed (ie. their next access will cause a page fault). This should
slow down Haiku a bit more, great, huh? :-)
* The page daemon currently only runs on low memory situations, though.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22156 a95241bf-73f2-0310-859d-f6bbb57e9c96
