ia64/linux-2.6.18-xen.hg

view arch/alpha/boot/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 # arch/alpha/boot/Makefile
3 #
4 # This file is subject to the terms and conditions of the GNU General Public
5 # License. See the file "COPYING" in the main directory of this archive
6 # for more details.
7 #
8 # Copyright (C) 1994 by Linus Torvalds
9 #
11 hostprogs-y := tools/mkbb tools/objstrip
12 targets := vmlinux.gz vmlinux \
13 vmlinux.nh tools/lxboot tools/bootlx tools/bootph \
14 tools/bootpzh bootloader bootpheader bootpzheader
15 OBJSTRIP := $(obj)/tools/objstrip
17 # SRM bootable image. Copy to offset 512 of a partition.
18 $(obj)/bootimage: $(addprefix $(obj)/tools/,mkbb lxboot bootlx) $(obj)/vmlinux.nh
19 ( cat $(obj)/tools/lxboot $(obj)/tools/bootlx $(obj)/vmlinux.nh ) > $@
20 $(obj)/tools/mkbb $@ $(obj)/tools/lxboot
21 @echo ' Bootimage $@ is ready'
23 # BOOTP bootable image. Define INITRD during make to append initrd image.
24 $(obj)/bootpfile: $(obj)/tools/bootph $(obj)/vmlinux.nh
25 cat $(obj)/tools/bootph $(obj)/vmlinux.nh > $@
26 ifdef INITRD
27 cat $(INITRD) >> $@
28 endif
30 # Compressed kernel BOOTP bootable image.
31 # Define INITRD during make to append initrd image.
32 $(obj)/bootpzfile: $(obj)/tools/bootpzh $(obj)/vmlinux.nh.gz
33 cat $(obj)/tools/bootpzh $(obj)/vmlinux.nh.gz > $@
34 ifdef INITRD
35 cat $(INITRD) >> $@
36 endif
38 # Compressed kernel image
39 $(obj)/vmlinux.gz: $(obj)/vmlinux FORCE
40 $(call if_changed,gzip)
41 @echo ' Kernel $@ is ready'
43 $(obj)/main.o: $(obj)/ksize.h
44 $(obj)/bootp.o: $(obj)/ksize.h
45 $(obj)/bootpz.o: $(obj)/kzsize.h
47 $(obj)/ksize.h: $(obj)/vmlinux.nh FORCE
48 echo "#define KERNEL_SIZE `ls -l $(obj)/vmlinux.nh | awk '{print $$5}'`" > $@T
49 ifdef INITRD
50 [ -f $(INITRD) ] || exit 1
51 echo "#define INITRD_IMAGE_SIZE `ls -l $(INITRD) | awk '{print $$5}'`" >> $@T
52 endif
53 cmp -s $@T $@ || mv -f $@T $@
54 rm -f $@T
56 $(obj)/kzsize.h: $(obj)/vmlinux.nh.gz FORCE
57 echo "#define KERNEL_SIZE `ls -l $(obj)/vmlinux.nh | awk '{print $$5}'`" > $@T
58 echo "#define KERNEL_Z_SIZE `ls -l $(obj)/vmlinux.nh.gz | awk '{print $$5}'`" >> $@T
59 ifdef INITRD
60 [ -f $(INITRD) ] || exit 1
61 echo "#define INITRD_IMAGE_SIZE `ls -l $(INITRD) | awk '{print $$5}'`" >> $@T
62 endif
63 cmp -s $@T $@ || mv -f $@T $@
64 rm -f $@T
66 quiet_cmd_strip = STRIP $@
67 cmd_strip = $(STRIP) -o $@ $<
69 $(obj)/vmlinux: vmlinux FORCE
70 $(call if_changed,strip)
72 quiet_cmd_objstrip = OBJSTRIP $@
73 cmd_objstrip = $(OBJSTRIP) $(OSFLAGS_$(@F)) $< $@
75 OSFLAGS_vmlinux.nh := -v
76 OSFLAGS_lxboot := -p
77 OSFLAGS_bootlx := -vb
78 OSFLAGS_bootph := -vb
79 OSFLAGS_bootpzh := -vb
81 $(obj)/vmlinux.nh: vmlinux $(OBJSTRIP) FORCE
82 $(call if_changed,objstrip)
84 $(obj)/vmlinux.nh.gz: $(obj)/vmlinux.nh FORCE
85 $(call if_changed,gzip)
87 $(obj)/tools/lxboot: $(obj)/bootloader $(OBJSTRIP) FORCE
88 $(call if_changed,objstrip)
90 $(obj)/tools/bootlx: $(obj)/bootloader $(OBJSTRIP) FORCE
91 $(call if_changed,objstrip)
93 $(obj)/tools/bootph: $(obj)/bootpheader $(OBJSTRIP) FORCE
94 $(call if_changed,objstrip)
96 $(obj)/tools/bootpzh: $(obj)/bootpzheader $(OBJSTRIP) FORCE
97 $(call if_changed,objstrip)
99 LDFLAGS_bootloader := -static -uvsprintf -T #-N -relax
100 LDFLAGS_bootpheader := -static -uvsprintf -T #-N -relax
101 LDFLAGS_bootpzheader := -static -uvsprintf -T #-N -relax
103 OBJ_bootlx := $(obj)/head.o $(obj)/main.o
104 OBJ_bootph := $(obj)/head.o $(obj)/bootp.o
105 OBJ_bootpzh := $(obj)/head.o $(obj)/bootpz.o $(obj)/misc.o
107 $(obj)/bootloader: $(obj)/bootloader.lds $(OBJ_bootlx) FORCE
108 $(call if_changed,ld)
110 $(obj)/bootpheader: $(obj)/bootloader.lds $(OBJ_bootph) $(LIBS_Y) FORCE
111 $(call if_changed,ld)
113 $(obj)/bootpzheader: $(obj)/bootloader.lds $(OBJ_bootpzh) $(LIBS_Y) FORCE
114 $(call if_changed,ld)
116 $(obj)/misc.o: lib/inflate.c