Magellan Linux

  • Back to homepage
    • /[pkg-src]/trunk/kernel26-alx/patches-2.6.20-r6/0017-2.6.20-mm-lots_watermark.diff

    Contents of /trunk/kernel26-alx/patches-2.6.20-r6/0017-2.6.20-mm-lots_watermark.diff

    Parent Directory Parent Directory | Revision Log Revision Log

    Revision 1175 - (show annotations) (download)
    Thu Oct 14 12:15:46 2010 UTC (13 years, 6 months ago) by niro
    File size: 4042 byte(s) 
    -2.6.20-alx-r6 new magellan 0.5.2 kernel
    1 The vm currently performs scanning when allocating ram once the watermarks
    2 are below the pages_low value and tries to restore them to the pages_high
    3 watermark. The disadvantage of this is that we are scanning most aggresssively
    4 at the same time we are allocating ram regardless of the stress the vm is
    5 under. Add a pages_lots watermark and allow the watermark to be relaxed
    6 according to the stress the vm is at the time (according to the priority
    7 value). Thus we have more in reserve next time we are allocating ram and end
    8 up scanning less aggresssively. Note the actual pages_lots isn't used directly
    9 in this code.
    10
    11 Signed-off-by: Con Kolivas <kernel@kolivas.org>
    12
    13 include/linux/mmzone.h | 2 +-
    14 mm/page_alloc.c | 3 +++
    15 mm/vmscan.c | 17 ++++++++++++++---
    16 3 files changed, 18 insertions(+), 4 deletions(-)
    17
    18 Index: linux-2.6.20-ck1/include/linux/mmzone.h
    19 ===================================================================
    20 --- linux-2.6.20-ck1.orig/include/linux/mmzone.h 2007-02-05 22:52:04.000000000 +1100
    21 +++ linux-2.6.20-ck1/include/linux/mmzone.h 2007-02-16 19:01:33.000000000 +1100
    22 @@ -156,7 +156,7 @@ enum zone_type {
    23 struct zone {
    24 /* Fields commonly accessed by the page allocator */
    25 unsigned long free_pages;
    26 - unsigned long pages_min, pages_low, pages_high;
    27 + unsigned long pages_min, pages_low, pages_high, pages_lots;
    28 /*
    29 * We don't know if the memory that we're going to allocate will be freeable
    30 * or/and it will be released eventually, so to avoid totally wasting several
    31 Index: linux-2.6.20-ck1/mm/page_alloc.c
    32 ===================================================================
    33 --- linux-2.6.20-ck1.orig/mm/page_alloc.c 2007-02-05 22:52:04.000000000 +1100
    34 +++ linux-2.6.20-ck1/mm/page_alloc.c 2007-02-16 19:01:33.000000000 +1100
    35 @@ -1604,6 +1604,7 @@ void show_free_areas(void)
    36 " min:%lukB"
    37 " low:%lukB"
    38 " high:%lukB"
    39 + " lots:%lukB"
    40 " active:%lukB"
    41 " inactive:%lukB"
    42 " present:%lukB"
    43 @@ -1615,6 +1616,7 @@ void show_free_areas(void)
    44 K(zone->pages_min),
    45 K(zone->pages_low),
    46 K(zone->pages_high),
    47 + K(zone->pages_lots),
    48 K(zone->nr_active),
    49 K(zone->nr_inactive),
    50 K(zone->present_pages),
    51 @@ -3149,6 +3151,7 @@ void setup_per_zone_pages_min(void)
    52
    53 zone->pages_low = zone->pages_min + (tmp >> 2);
    54 zone->pages_high = zone->pages_min + (tmp >> 1);
    55 + zone->pages_lots = zone->pages_min + tmp;
    56 spin_unlock_irqrestore(&zone->lru_lock, flags);
    57 }
    58
    59 Index: linux-2.6.20-ck1/mm/vmscan.c
    60 ===================================================================
    61 --- linux-2.6.20-ck1.orig/mm/vmscan.c 2007-02-16 19:01:33.000000000 +1100
    62 +++ linux-2.6.20-ck1/mm/vmscan.c 2007-02-16 19:01:33.000000000 +1100
    63 @@ -1172,6 +1172,7 @@ loop_again:
    64 */
    65 for (i = pgdat->nr_zones - 1; i >= 0; i--) {
    66 struct zone *zone = pgdat->node_zones + i;
    67 + unsigned long watermark;
    68
    69 if (!populated_zone(zone))
    70 continue;
    71 @@ -1179,8 +1180,14 @@ loop_again:
    72 if (zone->all_unreclaimable && priority != DEF_PRIORITY)
    73 continue;
    74
    75 - if (!zone_watermark_ok(zone, order, zone->pages_high,
    76 - 0, 0)) {
    77 + /*
    78 + * The watermark is relaxed depending on the
    79 + * level of "priority" till it drops to
    80 + * pages_high.
    81 + */
    82 + watermark = zone->pages_high + (zone->pages_high *
    83 + priority / DEF_PRIORITY);
    84 + if (!zone_watermark_ok(zone, order, watermark, 0, 0)) {
    85 end_zone = i;
    86 break;
    87 }
    88 @@ -1206,6 +1213,7 @@ loop_again:
    89 for (i = 0; i <= end_zone; i++) {
    90 struct zone *zone = pgdat->node_zones + i;
    91 int nr_slab;
    92 + unsigned long watermark;
    93
    94 if (!populated_zone(zone))
    95 continue;
    96 @@ -1213,7 +1221,10 @@ loop_again:
    97 if (zone->all_unreclaimable && priority != DEF_PRIORITY)
    98 continue;
    99
    100 - if (!zone_watermark_ok(zone, order, zone->pages_high,
    101 + watermark = zone->pages_high + (zone->pages_high *
    102 + priority / DEF_PRIORITY);
    103 +
    104 + if (!zone_watermark_ok(zone, order, watermark,
    105 end_zone, 0))
    106 all_zones_ok = 0;
    107 temp_priority[i] = priority;