ia64/linux-2.6.18-xen.hg

view arch/ia64/Makefile @ 897:329ea0ccb344

balloon: try harder to balloon up under memory pressure.

Currently if the balloon driver is unable to increase the guest's
reservation it assumes the failure was due to reaching its full
allocation, gives up on the ballooning operation and records the limit
it reached as the "hard limit". The driver will not try again until
the target is set again (even to the same value).

However it is possible that ballooning has in fact failed due to
memory pressure in the host and therefore it is desirable to keep
attempting to reach the target in case memory becomes available. The
most likely scenario is that some guests are ballooning down while
others are ballooning up and therefore there is temporary memory
pressure while things stabilise. You would not expect a well behaved
toolstack to ask a domain to balloon to more than its allocation nor
would you expect it to deliberately over-commit memory by setting
balloon targets which exceed the total host memory.

This patch drops the concept of a hard limit and causes the balloon
driver to retry increasing the reservation on a timer in the same
manner as when decreasing the reservation.

Also if we partially succeed in increasing the reservation
(i.e. receive less pages than we asked for) then we may as well keep
those pages rather than returning them to Xen.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Fri Jun 05 14:01:20 2009 +0100 (2009-06-05)
parents a533be77c572
children
line source
1 #
2 # ia64/Makefile
3 #
4 # This file is included by the global makefile so that you can add your own
5 # architecture-specific flags and dependencies.
6 #
7 # This file is subject to the terms and conditions of the GNU General Public
8 # License. See the file "COPYING" in the main directory of this archive
9 # for more details.
10 #
11 # Copyright (C) 1998-2004 by David Mosberger-Tang <davidm@hpl.hp.com>
12 #
14 NM := $(CROSS_COMPILE)nm -B
15 READELF := $(CROSS_COMPILE)readelf
17 export AWK
19 CHECKFLAGS += -m64 -D__ia64=1 -D__ia64__=1 -D_LP64 -D__LP64__
21 OBJCOPYFLAGS := --strip-all
22 LDFLAGS_vmlinux := -static
23 LDFLAGS_MODULE += -T $(srctree)/arch/ia64/module.lds
24 AFLAGS_KERNEL := -mconstant-gp
25 EXTRA :=
27 cflags-y := -pipe $(EXTRA) -ffixed-r13 -mfixed-range=f12-f15,f32-f127 \
28 -falign-functions=32 -frename-registers -fno-optimize-sibling-calls
29 CFLAGS_KERNEL := -mconstant-gp
31 GAS_STATUS = $(shell $(srctree)/arch/ia64/scripts/check-gas "$(CC)" "$(OBJDUMP)")
32 CPPFLAGS += $(shell $(srctree)/arch/ia64/scripts/toolchain-flags "$(CC)" "$(OBJDUMP)" "$(READELF)")
34 ifeq ($(GAS_STATUS),buggy)
35 $(error Sorry, you need a newer version of the assember, one that is built from \
36 a source-tree that post-dates 18-Dec-2002. You can find a pre-compiled \
37 static binary of such an assembler at: \
38 \
39 ftp://ftp.hpl.hp.com/pub/linux-ia64/gas-030124.tar.gz)
40 endif
42 ifeq ($(call cc-version),0304)
43 cflags-$(CONFIG_ITANIUM) += -mtune=merced
44 cflags-$(CONFIG_MCKINLEY) += -mtune=mckinley
45 endif
47 CFLAGS += $(cflags-y)
49 cppflags-$(CONFIG_XEN) += \
50 -D__XEN_INTERFACE_VERSION__=$(CONFIG_XEN_INTERFACE_VERSION)
52 CPPFLAGS += $(cppflags-y)
54 head-y := arch/ia64/kernel/head.o arch/ia64/kernel/init_task.o
56 libs-y += arch/ia64/lib/
57 core-y += arch/ia64/kernel/ arch/ia64/mm/
58 core-$(CONFIG_IA32_SUPPORT) += arch/ia64/ia32/
59 core-$(CONFIG_IA64_DIG) += arch/ia64/dig/
60 core-$(CONFIG_IA64_GENERIC) += arch/ia64/dig/
61 core-$(CONFIG_IA64_HP_ZX1) += arch/ia64/dig/
62 core-$(CONFIG_IA64_HP_ZX1_SWIOTLB) += arch/ia64/dig/
63 core-$(CONFIG_IA64_XEN) += arch/ia64/dig/
64 core-$(CONFIG_IA64_SGI_SN2) += arch/ia64/sn/
65 core-$(CONFIG_XEN) += arch/ia64/xen/
67 drivers-$(CONFIG_PCI) += arch/ia64/pci/
68 drivers-$(CONFIG_IA64_HP_SIM) += arch/ia64/hp/sim/
69 drivers-$(CONFIG_IA64_HP_ZX1) += arch/ia64/hp/common/ arch/ia64/hp/zx1/
70 drivers-$(CONFIG_IA64_HP_ZX1_SWIOTLB) += arch/ia64/hp/common/ arch/ia64/hp/zx1/
71 drivers-$(CONFIG_IA64_GENERIC) += arch/ia64/hp/common/ arch/ia64/hp/zx1/ arch/ia64/hp/sim/ arch/ia64/sn/
72 drivers-$(CONFIG_OPROFILE) += arch/ia64/oprofile/
74 boot := arch/ia64/hp/sim/boot
76 PHONY += boot compressed check
78 all: compressed unwcheck
80 compressed: vmlinux.gz
82 vmlinuz: vmlinux.gz
84 vmlinux.gz: vmlinux
85 $(Q)$(MAKE) $(build)=$(boot) $@
87 unwcheck: vmlinux
88 -$(Q)READELF=$(READELF) $(srctree)/arch/ia64/scripts/unwcheck.py $<
90 archclean:
91 $(Q)$(MAKE) $(clean)=$(boot)
93 CLEAN_FILES += vmlinux.gz bootloader
95 boot: lib/lib.a vmlinux
96 $(Q)$(MAKE) $(build)=$(boot) $@
98 install:
99 -yes | sh $(srctree)/arch/ia64/install.sh $(KERNELRELEASE) vmlinux.gz System.map "$(INSTALL_PATH)"
101 define archhelp
102 echo '* compressed - Build compressed kernel image'
103 echo ' install - Install compressed kernel image'
104 echo ' boot - Build vmlinux and bootloader for Ski simulator'
105 echo '* unwcheck - Check vmlinux for invalid unwind info'
106 endef