From 7ba2ea0371b556e3441456dc7a95b7a897b26249 Mon Sep 17 00:00:00 2001 From: alc Date: Sat, 11 Apr 2009 09:09:00 +0000 Subject: Previously, when vm_page_free_toq() was performed on a page belonging to a reservation, unless all of the reservation's pages were free, the reservation was moved to the head of the partially-populated reservations queue, where it would be the next reservation to be broken in case the free page queues were emptied. Now, instead, I am moving it to the tail. Very likely this reservation is in the process of being freed in its entirety, so placing it at the tail of the queue makes it more likely that the underlying physical memory will be returned to the free page queues as one contiguous chunk. If a reservation must be broken, it will, instead, be the longest unchanged reservation, which is arguably the reservation that is least likely to ever achieve promotion or be freed in its entirety. MFC after: 6 weeks --- sys/vm/vm_reserv.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'sys/vm') diff --git a/sys/vm/vm_reserv.c b/sys/vm/vm_reserv.c index 4ea9079..d9e908f 100644 --- a/sys/vm/vm_reserv.c +++ b/sys/vm/vm_reserv.c @@ -138,8 +138,8 @@ static vm_reserv_t vm_reserv_array; * The partially-populated reservation queue * * This queue enables the fast recovery of an unused cached or free small page - * from a partially-populated reservation. The head of this queue is either - * the least-recently-populated or most-recently-depopulated reservation. + * from a partially-populated reservation. The reservation at the head of + * this queue is the least-recently-changed, partially-populated reservation. * * Access to this queue is synchronized by the free page queue lock. */ @@ -209,7 +209,7 @@ sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS) /* * Reduces the given reservation's population count. If the population count * becomes zero, the reservation is destroyed. Additionally, moves the - * reservation to the head of the partially-populated reservations queue if the + * reservation to the tail of the partially-populated reservations queue if the * population count is non-zero. * * The free page queue lock must be held. @@ -235,7 +235,7 @@ vm_reserv_depopulate(vm_reserv_t rv) vm_reserv_freed++; } else { rv->inpartpopq = TRUE; - TAILQ_INSERT_HEAD(&vm_rvq_partpop, rv, partpopq); + TAILQ_INSERT_TAIL(&vm_rvq_partpop, rv, partpopq); } } -- cgit v1.1