From a5ab72bc176e679e362c9c6125e3e3da954263e7 Mon Sep 17 00:00:00 2001 From: Richard Braun Date: Wed, 12 May 2032 03:15:41 +0200 Subject: VM: fix pageout throttling to external pagers Since the VM system has been tracking whether pages belong to internal or external objects, pageout throttling to external pagers has simply not been working. The reason is that, on pageout, requests for external pages are correctly tracked, but on page release (which is used to acknowledge the request), external pages are not marked external any more. This is because the external bit tracks whether a page belongs to an external object, and all pages, including external ones, are moved to an internal object during pageout. To solve this issue, a new "external_laundry" bit is added. It has the same purpose as the laundry bit, but for external pagers. * vm/vm_page.c (vm_page_seg_min_page_available): Function unused, remove. (vm_page_seg_evict): Use vm_page_external_laundry_count instead of vm_page_external_pagedout. Add an assertion about double paging. (vm_page_check_usable): Use vm_page_external_laundry_count instead of vm_page_external_pagedout. (vm_page_evict): Likewise. * vm/vm_page.h (struct vm_page): New `external_laundry' member. (vm_page_external_pagedout): Rename to ... (vm_page_external_laundry_count): ... this. * vm/vm_pageout.c: Include kern/printf.h. (DEBUG): New macro. (VM_PAGEOUT_TIMEOUT): Likewise. (vm_pageout_setup): Use vm_page_external_laundry_count instead of vm_page_external_pagedout. Set `external_laundry' where appropriate. (vm_pageout): Use VM_PAGEOUT_TIMEOUT with thread_set_timeout. Add debugging code, commented out by default. * vm/vm_resident.c (vm_page_external_pagedout): Rename to ... (vm_page_external_laundry_count): ... this. (vm_page_init_template): Set `external_laundry' member to FALSE. (vm_page_release): Rename external parameter to external_laundry. Slightly change pageout resuming. (vm_page_free): Rename external variable to external_laundry. --- vm/vm_page.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'vm/vm_page.h') diff --git a/vm/vm_page.h b/vm/vm_page.h index eb684c1b..2a0ad2c2 100644 --- a/vm/vm_page.h +++ b/vm/vm_page.h @@ -105,6 +105,7 @@ struct vm_page { /* boolean_t */ inactive:1, /* page is in inactive list (P) */ active:1, /* page is in active list (P) */ laundry:1, /* page is being cleaned now (P)*/ + external_laundry:1, /* same as laundry for external pagers (P)*/ free:1, /* page is on free list (P) */ reference:1, /* page has been used (P) */ external:1, /* page in external object (P) */ @@ -165,7 +166,7 @@ int vm_page_wire_count; /* How many pages are wired? */ extern int vm_page_laundry_count; /* How many pages being laundered? */ extern -int vm_page_external_pagedout; /* How many external pages being paged out? */ +int vm_page_external_laundry_count; /* How many external pages being paged out? */ decl_simple_lock_data(extern,vm_page_queue_lock)/* lock on active and inactive page queues */ -- cgit v1.2.3