ia64/linux-2.6.18-xen.hg

view arch/sparc/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 831230e53067
children
line source
1 #
2 # sparc/Makefile
3 #
4 # Makefile for the architecture dependent flags and dependencies on the
5 # Sparc.
6 #
7 # Copyright (C) 1994 David S. Miller (davem@caip.rutgers.edu)
8 #
10 #
11 # Uncomment the first CFLAGS if you are doing kgdb source level
12 # debugging of the kernel to get the proper debugging information.
14 AS := $(AS) -32
15 LDFLAGS := -m elf32_sparc
16 CHECKFLAGS += -D__sparc__
18 #CFLAGS := $(CFLAGS) -g -pipe -fcall-used-g5 -fcall-used-g7
19 CFLAGS := $(CFLAGS) -m32 -pipe -mno-fpu -fcall-used-g5 -fcall-used-g7
20 AFLAGS := $(AFLAGS) -m32
22 #LDFLAGS_vmlinux = -N -Ttext 0xf0004000
23 # Since 2.5.40, the first stage is left not btfix-ed.
24 # Actual linking is done with "make image".
25 LDFLAGS_vmlinux = -r
27 head-y := arch/sparc/kernel/head.o arch/sparc/kernel/init_task.o
28 HEAD_Y := $(head-y)
30 core-y += arch/sparc/kernel/ arch/sparc/mm/ arch/sparc/math-emu/
31 libs-y += arch/sparc/prom/ arch/sparc/lib/
33 # Export what is needed by arch/sparc/boot/Makefile
34 # Renaming is done to avoid confusing pattern matching rules in 2.5.45 (multy-)
35 INIT_Y := $(patsubst %/, %/built-in.o, $(init-y))
36 CORE_Y := $(core-y)
37 CORE_Y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
38 CORE_Y := $(patsubst %/, %/built-in.o, $(CORE_Y))
39 DRIVERS_Y := $(patsubst %/, %/built-in.o, $(drivers-y))
40 NET_Y := $(patsubst %/, %/built-in.o, $(net-y))
41 LIBS_Y1 := $(patsubst %/, %/lib.a, $(libs-y))
42 LIBS_Y2 := $(patsubst %/, %/built-in.o, $(libs-y))
43 LIBS_Y := $(LIBS_Y1) $(LIBS_Y2)
45 ifdef CONFIG_KALLSYMS
46 kallsyms.o := .tmp_kallsyms2.o
47 endif
49 export INIT_Y CORE_Y DRIVERS_Y NET_Y LIBS_Y HEAD_Y kallsyms.o
51 # Default target
52 all: image
54 boot := arch/sparc/boot
56 image tftpboot.img: vmlinux
57 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
59 archclean:
60 $(Q)$(MAKE) $(clean)=$(boot)
62 CLEAN_FILES += arch/$(ARCH)/boot/System.map
64 # Don't use tabs in echo arguments.
65 define archhelp
66 echo '* image - kernel image ($(boot)/image)'
67 echo ' tftpboot.img - image prepared for tftp'
68 endef