merge r2889, r2918, and r2921:

fix a pool growing and CPU usage for multi-requests keepalive connections:

*) keepalive_requests
*) try to reuse last 4 free large allocation links
*) do not test a pool block space if we can not allocated from
   the block 4 times

1 files changed, 17 insertions, 1 deletions

diff --git a/src/core/ngx_palloc.c b/src/core/ngx_palloc.c
index 3e1c9f2ad..fd0476803 100644
--- a/src/core/ngx_palloc.c
+++ b/src/core/ngx_palloc.c
@@ -25,6 +25,7 @@ ngx_create_pool(size_t size, ngx_log_t *log)
     p->d.last = (u_char *) p + sizeof(ngx_pool_t);
     p->d.end = (u_char *) p + size;
     p->d.next = NULL;
+    p->d.failed = 0;
 
     size = size - sizeof(ngx_pool_t);
     p->max = (size < NGX_MAX_ALLOC_FROM_POOL) ? size : NGX_MAX_ALLOC_FROM_POOL;
@@ -189,6 +190,7 @@ ngx_palloc_block(ngx_pool_t *pool, size_t size)
 
     new->d.end = m + psize;
     new->d.next = NULL;
+    new->d.failed = 0;
 
     m += sizeof(ngx_pool_data_t);
     m = ngx_align_ptr(m, NGX_ALIGNMENT);
@@ -197,7 +199,7 @@ ngx_palloc_block(ngx_pool_t *pool, size_t size)
     current = pool->current;
 
     for (p = current; p->d.next; p = p->d.next) {
-        if ((size_t) (p->d.end - p->d.last) < NGX_ALIGNMENT) {
+        if (p->d.failed++ > 4) {
             current = p->d.next;
         }
     }
@@ -214,6 +216,7 @@ static void *
 ngx_palloc_large(ngx_pool_t *pool, size_t size)
 {
     void              *p;
+    ngx_uint_t         n;
     ngx_pool_large_t  *large;
 
     p = ngx_alloc(size, pool->log);
@@ -221,6 +224,19 @@ ngx_palloc_large(ngx_pool_t *pool, size_t size)
         return NULL;
     }
 
+    n = 0;
+
+    for (large = pool->large; large; large = large->next) {
+        if (large->alloc == NULL) {
+            large->alloc = p;
+            return p;
+        }
+
+        if (n++ > 3) {
+            break;
+        }
+    }
+
     large = ngx_palloc(pool, sizeof(ngx_pool_large_t));
     if (large == NULL) {
         ngx_free(p);