维护100亿个URL(Radix TRee)

1intmc_radix_hash_insert(mc_radix_t*t,unsignedinthashvalue,void*data,size_tsize)
2{
3unsignedinti=0;
4mc_radix_node_t*root=t->root;
5
6if(t->root==NULL)
7{
8t->root=mc_get_radix_node(t->nodes);
9}
10
11/*LRU*/
12/*其中涉及到LRU算法，原理是将所有的叶子节点链接为双向队列，然后更新和插入放入队列头，按照一定的比例从队列尾删除数据*/
13if(t->queue.cur_num>=(t->queue.max_num)*PERCENT)
14{
15for(i=0;i<(t->queue.max_num)*(1-PERCENT);i++)
16{
17mc_del_item(t,t->queue.pear);
18}
19}
20mc_radix_node_t*cur=t->root;
21for(i=0;i<32;i++)
22{
23/*1--->right*/
24　　　　/*按位来探测树节点*/
25if(hashvalue&MASKARRAY[i])
26{
27
28if(cur->right!=NULL)
29{
30cur->used_num++;
31cur->right->parent=cur;
32cur=cur->right;
33}
34else
35{
36cur->right=mc_get_radix_node(t->nodes);
37if(cur->right==NULL)
38{
39fprintf(stderr,"mc_get_radix_nodeerror\n");
40return-1;
41}
42cur->used_num++;
43cur->right->parent=cur;
44cur=cur->right;
45}
46}
47/*0--->left*/
48else
49{
50
51if(cur->left!=NULL)
52{
53cur->used_num++;
54cur->left->parent=cur;
55cur=cur->left;
56}
57else
58{
59cur->left=mc_get_radix_node(t->nodes);
60if(cur->left==NULL)
61{
62fprintf(stderr,"mc_get_radix_nodeerror\n");
63return-1;
64}
65
66cur->used_num++;
67cur->left->parent=cur;
68cur=cur->left;
69}
70}
71}
72
73t->totalnum++;
74mc_slot_t*l_slot=mc_slot_alloc(t->slab,size);
75cur->data=(mc_slot_t*)(cur->data);
76memcpy(l_slot->star,data,size);
77cur->data=l_slot;
78
79/*addtot->queue*/
80if(t->queue.head==NULL)
81{
82t->queue.head=cur;
83t->queue.pear=cur;
84cur->left=NULL;
85cur->right=NULL;
86
87t->queue.cur_num++;
88}
89else
90{
91cur->left=NULL;
92cur->right=t->queue.head;
93t->queue.head->left=cur;
94t->queue.head=cur;
95
96t->queue.cur_num++;
97}
98return1;
99}

1intmc_radix_hash_del(mc_radix_t*t,unsignedinthashvalue)
2{
3if(t==NULL||t->root==NULL)
4{
5return-1;
6}
7/*noninitialized*/
8if(t->magic!=MC_MAGIC)
9{
10return-1;
11}
12mc_radix_node_t*cur=t->root;
13mc_radix_node_t*cur_par;
14inti=0;
15for(;i<32;i++)
16{
17if(hashvalue&MASKARRAY[i])
18{
19
20if(cur->right!=NULL)
21{
22cur->used_num--;
23cur=cur->right;
24}
25else
26return-1;
27}
28else
29{
30
31if(cur->left!=NULL)
32{
33cur->used_num--;
34cur=cur->left;
35}
36else
37return-1;
38}
39}
40
41if(cur->used_num>=0)
42mc_slot_free(cur->data);
43
44/*removefromt->queue*/
45if(cur==t->queue.pear&&cur==t->queue.head)
46{
47t->queue.pear=NULL;
48t->queue.head=NULL;
49t->queue.cur_num--;
50}
51/*thelastitem*/
52elseif(cur==t->queue.pear&&cur!=t->queue.head)
53{
54cur->left->right=NULL;
55cur->left=NULL;
56t->queue.cur_num--;
57}
58elseif(cur!=t->queue.pear)
59{
60cur->left->right=cur->right;
61cur->right->left=cur->left;
62t->queue.cur_num--;
63}
64else
65{
66cur->left->right=cur->right;
67cur->right->left=cur->left;
68t->queue.cur_num--;
69}
70
71for(;;)
72{
73
74if(cur->used_num==0)
75{
76cur_par=cur->parent;
77mc_free_radix_node(t->nodes,cur);
78cur=cur_par;
79}
80if(cur==NULL)
81break;
82if(cur->used_num>0)
83break;
84
85}
86
87return1;
88
89}

1void*mc_radix_hash_get(mc_radix_t*t,unsignedinthashvalue)
2{
3if(t==NULL||t->root==NULL)
4{
5fprintf(stderr,"t==NULL||t->root==NULL\n");
6return(void*)(0);
7}
8/*noninitialized*/
9if(t->magic!=MC_MAGIC)
10{
11fprintf(stderr,"t->magic!=MC_MAGIC\n");
12return(void*)(0);
13}
14mc_radix_node_t*cur=t->root;
15mc_slot_t*ret_slot;
16inti=0;
17for(;i<32;i++)
18{
19if(hashvalue&MASKARRAY[i])
20{
21if(cur->right==NULL)
22break;
23else
24cur=cur->right;
25}
26else
27{
28if(cur->left==NULL)
29break;
30else
31cur=cur->left;
32}
33}
34if(i==32)
35{
36ret_slot=cur->data;
37
38/*updateLRUqueue*/
39if(cur->left!=NULL)
40{
41if(cur->right!=NULL)
42{
43cur->left->right=cur->right;
44cur->right->left=cur->left;
45cur->left=t->queue.head;
46t->queue.head->left=cur;
47t->queue.head=cur;
48}
49else
50{
51/*cur->right==NULLlastelementofLRUqueue*/
52cur->left->right=NULL;
53cur->left=t->queue.head;
54t->queue.head->left=cur;
55t->queue.head=cur;
56
57}
58}
59return(void*)(ret_slot->star);
60}
61else
62{
63fprintf(stderr,"i=%d\n",i);
64return(void*)(0);
65}
66}

1intmc_free_radix(mc_radix_t*t)
2{
3mc_free_all_radix_node(t->nodes);
4mc_slab_free(t->slab);
5free(t->nodes);
6}
7
8staticvoidmc_del_item(mc_radix_t*t,mc_radix_node_t*cur)
9{
10if(cur->left==NULL)
11{
12fprintf(stderr,"itemnumberinLRUqueueistoosmall\n");
13return;
14}
15if(cur->right!=NULL)
16{
17fprintf(stderr,"curshouldbethelastofLRUqueue\n");
18}
19/*removefromLRUqueue*/
20mc_radix_node_t*pcur=cur->left;
21cur->left=NULL;
22pcur->right=NULL;
23
24pcur=cur->parent;
25/*removefromradixtree*/
26while(pcur!=NULL)
27{
28cur->used_num--;
29if(cur->used_num<=0)
30{
31mc_free_radix_node(t->nodes,cur);
32}
33cur=pcur;
34pcur=pcur->parent;
35}
36
37}

geo$country{
defaultno;
127.0.0.0/24us;#/之前为IP地址address，/之后是地址掩码mask
127.0.0.1/32ru;
10.1.0.0/16ru;
192.168.1.0/24uk;#当ip地址为192.168.1.23时，变量country的值为uk
}

01

typedef

struct

ngx_radix_node_s
ngx_radix_node_t;

02

03

struct

ngx_radix_node_s
{

04

ngx_radix_node_t
*right;

05

ngx_radix_node_t
*left;

06

ngx_radix_node_t
*parent;

07

uintptr_t

value;

08

};

09

10

typedef

struct

{

11

ngx_radix_node_t
*root;

12

ngx_pool_t
*pool;

13

ngx_radix_node_t
*

free

;

14

char

*start;

15

size_t

size;

16

}
ngx_radix_tree_t;

1

ngx_radix_tree_t
*ngx_radix_tree_create(ngx_pool_t*pool,

2

ngx_int_t
preallocate);

3

ngx_int_t
ngx_radix32tree_insert(ngx_radix_tree_t*tree,

4

uint32_t
key,uint32_tmask,

uintptr_t

value);

5

ngx_int_t
ngx_radix32tree_delete(ngx_radix_tree_t*tree,

6

uint32_t
key,uint32_tmask);

7

uintptr_t

ngx_radix32tree_find(ngx_radix_tree_t
*tree,uint32_tkey);

01

/*

02

*
Preallocationoffirstnodes:0,1,00,01,10,11,000,001,etc.

03

*
increasesTLBhitsevenifforfirstlookupiterations.

04

*
On32-bitplatformsthe7preallocatedbitstakescontinuous4K,

05

*
8-8K,9-16K,etc.On64-bitplatformsthe6preallocatedbits

06

*
takescontinuous4K,7-8K,8-16K,etc.Thereisnosenseto

07

*
topreallocatemorethanonepage,becausefurtherpreallocation

08

*
distributestheonlybitperpage.Instead,arandominsertion

09

*
maydistributeseveralbitsperpage.

10

*

11

*
Thus,bydefaultwepreallocatemaximum

12

*
6bitsonamd64(64-bitplatformand4Kpages)

13

*
7bitsoni386(32-bitplatformand4Kpages)

14

*
7bitsonsparc64in64-bitmode(8Kpages)

15

*
8bitsonsparc64in32-bitmode(8Kpages)

16

*/

01

uintptr_t

02

ngx_radix32tree_find(ngx_radix_tree_t
*tree,uint32_tkey)

03

{

04

uint32_t
bit;

05

uintptr_t

value;

06

ngx_radix_node_t
*node;

07

08

bit
=0x80000000;

09

value
=NGX_RADIX_NO_VALUE;

10

node
=tree->root;

11

12

while

(node)
{

13

if

(node->value
!=NGX_RADIX_NO_VALUE){

14

value
=node->value;

15

}

16

17

if

(key
&bit){

18

node
=node->right;

19

20

}

else

{

21

node
=node->left;

22

}

23

24

bit
>>=1;

25

}

26

27

return

value;

28

}