Mercurial > hg > nginx-quic
annotate src/core/ngx_murmurhash.c @ 4385:70ba81827472
Cache locks initial implementation.
New directives: proxy_cache_lock on/off, proxy_cache_lock_timeout. With
proxy_cache_lock set to on, only one request will be allowed to go to
upstream for a particular cache item. Others will wait for a response
to appear in cache (or cache lock released) up to proxy_cache_lock_timeout.
Waiting requests will recheck if they have cached response ready (or are
allowed to run) every 500ms.
Note: we intentionally don't intercept NGX_DECLINED possibly returned by
ngx_http_file_cache_read(). This needs more work (possibly safe, but needs
further investigation). Anyway, it's exceptional situation.
Note: probably there should be a way to disable caching of responses
if there is already one request fetching resource to cache (without waiting
at all). Two possible ways include another cache lock option ("no_cache")
or using proxy_no_cache with some supplied variable.
Note: probably there should be a way to lock updating requests as well. For
now "proxy_cache_use_stale updating" is available.
| author | Maxim Dounin <mdounin@mdounin.ru> |
|---|---|
| date | Mon, 26 Dec 2011 11:15:23 +0000 |
| parents | 203eb026ec07 |
| children | f38647c651a8 |
| rev | line source |
|---|---|
| 3891 | 1 |
| 2 /* | |
| 3 * Copyright (C) Austin Appleby | |
| 4 */ | |
| 5 | |
| 6 | |
| 7 #include <ngx_config.h> | |
| 8 #include <ngx_core.h> | |
| 9 | |
| 10 | |
| 11 uint32_t | |
| 12 ngx_murmur_hash2(u_char *data, size_t len) | |
| 13 { | |
| 14 uint32_t h, k; | |
| 15 | |
| 16 h = 0 ^ len; | |
| 17 | |
| 18 while (len >= 4) { | |
| 19 k = data[0]; | |
| 20 k |= data[1] << 8; | |
| 21 k |= data[2] << 16; | |
| 22 k |= data[3] << 24; | |
| 23 | |
| 24 k *= 0x5bd1e995; | |
| 25 k ^= k >> 24; | |
| 26 k *= 0x5bd1e995; | |
| 27 | |
| 28 h *= 0x5bd1e995; | |
| 29 h ^= k; | |
| 30 | |
| 31 data += 4; | |
| 32 len -= 4; | |
| 33 } | |
| 34 | |
| 35 switch (len) { | |
| 36 case 3: | |
| 37 h ^= data[2] << 16; | |
| 38 case 2: | |
| 39 h ^= data[1] << 8; | |
| 40 case 1: | |
| 41 h ^= data[0]; | |
| 42 h *= 0x5bd1e995; | |
| 43 } | |
| 44 | |
| 45 h ^= h >> 13; | |
| 46 h *= 0x5bd1e995; | |
| 47 h ^= h >> 15; | |
| 48 | |
| 49 return h; | |
| 50 } |