view drivers/net/ixp2000/ixp2400_rx.ucode @ 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
line source
1 static struct ixp2000_uengine_code ixp2400_rx =
2 {
3 .cpu_model_bitmask = 0x000003fe,
4 .cpu_min_revision = 0,
5 .cpu_max_revision = 255,
7 .uengine_parameters = IXP2000_UENGINE_8_CONTEXTS |
14 .initial_reg_values = (struct ixp2000_reg_value []) {
15 { -1, -1 }
16 },
18 .num_insns = 109,
19 .insns = (u8 []) {
20 0xf0, 0x00, 0x0c, 0xc0, 0x05,
21 0xf4, 0x44, 0x0c, 0x00, 0x05,
22 0xfc, 0x04, 0x4c, 0x00, 0x00,
23 0xf0, 0x00, 0x00, 0x3b, 0x00,
24 0xb4, 0x40, 0xf0, 0x3b, 0x1f,
25 0x8a, 0xc0, 0x50, 0x3e, 0x05,
26 0xb4, 0x40, 0xf0, 0x3b, 0x80,
27 0x9a, 0xe0, 0x00, 0x3e, 0x05,
28 0xf0, 0x00, 0x00, 0x07, 0x00,
29 0xd8, 0x05, 0xc0, 0x00, 0x11,
30 0xf0, 0x00, 0x00, 0x0f, 0x00,
31 0x91, 0xb0, 0x20, 0x0e, 0x00,
32 0xfc, 0x06, 0x60, 0x0b, 0x00,
33 0xf0, 0x00, 0x0c, 0x03, 0x00,
34 0xf0, 0x00, 0x0c, 0x03, 0x00,
35 0xf0, 0x00, 0x0c, 0x03, 0x00,
36 0xf0, 0x00, 0x0c, 0x02, 0x00,
37 0xb0, 0xc0, 0x30, 0x0f, 0x01,
38 0xa4, 0x70, 0x00, 0x0f, 0x20,
39 0xd8, 0x02, 0xc0, 0x01, 0x00,
40 0xfc, 0x10, 0xac, 0x23, 0x08,
41 0xfc, 0x10, 0xac, 0x43, 0x10,
42 0xfc, 0x10, 0xac, 0x63, 0x18,
43 0xe0, 0x00, 0x00, 0x00, 0x02,
44 0xfc, 0x10, 0xae, 0x23, 0x88,
45 0x3d, 0x00, 0x04, 0x03, 0x20,
46 0xe0, 0x00, 0x00, 0x00, 0x10,
47 0x84, 0x82, 0x02, 0x01, 0x3b,
48 0xd8, 0x1a, 0x00, 0x01, 0x01,
49 0xb4, 0x00, 0x8c, 0x7d, 0x80,
50 0x91, 0xb0, 0x80, 0x22, 0x00,
51 0xfc, 0x06, 0x60, 0x23, 0x00,
52 0xf0, 0x00, 0x0c, 0x03, 0x00,
53 0xf0, 0x00, 0x0c, 0x03, 0x00,
54 0xf0, 0x00, 0x0c, 0x03, 0x00,
55 0x94, 0xf0, 0x92, 0x01, 0x21,
56 0xac, 0x40, 0x60, 0x26, 0x00,
57 0xa4, 0x30, 0x0c, 0x04, 0x06,
58 0xd8, 0x1a, 0x40, 0x01, 0x00,
59 0x94, 0xe0, 0xa2, 0x01, 0x21,
60 0xac, 0x20, 0x00, 0x28, 0x06,
61 0x84, 0xf2, 0x02, 0x01, 0x21,
62 0xd8, 0x0b, 0x40, 0x01, 0x00,
63 0xf0, 0x00, 0x0c, 0x02, 0x01,
64 0xf0, 0x00, 0x0c, 0x02, 0x02,
65 0xa0, 0x00, 0x08, 0x04, 0x00,
66 0x95, 0x00, 0xc6, 0x01, 0xff,
67 0xa0, 0x80, 0x10, 0x30, 0x00,
68 0xa0, 0x60, 0x1c, 0x00, 0x01,
69 0xf0, 0x0f, 0xf0, 0x33, 0xff,
70 0xb4, 0x00, 0xc0, 0x31, 0x81,
71 0xb0, 0x80, 0xb0, 0x32, 0x02,
72 0xa0, 0x20, 0x20, 0x2c, 0x00,
73 0x94, 0xf0, 0xd2, 0x01, 0x21,
74 0xd8, 0x0f, 0x40, 0x01, 0x00,
75 0x19, 0x40, 0x10, 0x04, 0x20,
76 0xa0, 0x00, 0x26, 0x04, 0x00,
77 0xd8, 0x0d, 0xc0, 0x01, 0x00,
78 0x00, 0x42, 0x10, 0x80, 0x02,
79 0xb0, 0x00, 0x46, 0x04, 0x00,
80 0xb0, 0x00, 0x56, 0x08, 0x00,
81 0xe0, 0x00, 0x00, 0x00, 0x04,
82 0xfc, 0x10, 0xae, 0x43, 0x90,
83 0x84, 0xf0, 0x32, 0x01, 0x21,
84 0xd8, 0x11, 0x40, 0x01, 0x00,
85 0xa0, 0x60, 0x3c, 0x00, 0x02,
86 0xa0, 0x20, 0x40, 0x10, 0x00,
87 0xa0, 0x20, 0x50, 0x14, 0x00,
88 0xd8, 0x12, 0x00, 0x00, 0x18,
89 0xa0, 0x00, 0x28, 0x0c, 0x00,
90 0xb0, 0x00, 0x48, 0x10, 0x00,
91 0xb0, 0x00, 0x58, 0x14, 0x00,
92 0xaa, 0xf0, 0x00, 0x14, 0x01,
93 0xd8, 0x1a, 0xc0, 0x01, 0x05,
94 0x85, 0x80, 0x42, 0x01, 0xff,
95 0x95, 0x00, 0x66, 0x01, 0xff,
96 0xba, 0xc0, 0x60, 0x1b, 0x01,
97 0x9a, 0x30, 0x60, 0x19, 0x30,
98 0x9a, 0xb0, 0x70, 0x1a, 0x30,
99 0x9b, 0x50, 0x78, 0x1e, 0x04,
100 0x8a, 0xe2, 0x08, 0x1e, 0x21,
101 0x6a, 0x4e, 0x00, 0x13, 0x00,
102 0xe0, 0x00, 0x00, 0x00, 0x30,
103 0x9b, 0x00, 0x7a, 0x92, 0x04,
104 0x3d, 0x00, 0x04, 0x1f, 0x20,
105 0x84, 0xe2, 0x02, 0x01, 0x21,
106 0xd8, 0x16, 0x80, 0x01, 0x00,
107 0xa4, 0x18, 0x0c, 0x7d, 0x80,
108 0xa0, 0x58, 0x1c, 0x00, 0x01,
109 0x01, 0x42, 0x00, 0xa0, 0x02,
110 0xe0, 0x00, 0x00, 0x00, 0x08,
111 0xfc, 0x10, 0xae, 0x63, 0x98,
112 0xd8, 0x1b, 0x00, 0xc2, 0x14,
113 0x84, 0xe2, 0x02, 0x01, 0x21,
114 0xd8, 0x05, 0xc0, 0x01, 0x00,
115 0x84, 0xa2, 0x02, 0x01, 0x21,
116 0xd8, 0x19, 0x40, 0x01, 0x01,
117 0xa0, 0x58, 0x0c, 0x00, 0x02,
118 0x1a, 0x40, 0x00, 0x04, 0x24,
119 0x33, 0x00, 0x01, 0x2f, 0x20,
120 0xd8, 0x05, 0xc0, 0x00, 0x18,
121 0xa0, 0x58, 0x0c, 0x00, 0x02,
122 0x1a, 0x40, 0x00, 0x04, 0x20,
123 0xd8, 0x05, 0xc0, 0x00, 0x18,
124 0xe0, 0x00, 0x02, 0x00, 0x00,
125 0xe0, 0x00, 0x02, 0x00, 0x00,
126 0xe0, 0x00, 0x02, 0x00, 0x00,
127 0xe0, 0x00, 0x02, 0x00, 0x00,
128 0xe0, 0x00, 0x02, 0x00, 0x00,
129 }
130 };