Merge of r3966, r3967, r3968, r3969, r3970, r3971:

Cache loader improvements:

The cache loader performs two tasks: inserting cache objects in inactivity
list and evaluating total cache size. Reading just directory is enough for
this purpose. Elimination of reading cache files saves at least one disk I/O
operation per file.

src/core/ngx_file.c

@@ -926,6 +926,7 @@ ngx_walk_tree(ngx_tree_ctx_t *ctx, ngx_str_t *tree)
                            "tree file \"%s\"", file.data);
 
             ctx->size = ngx_de_size(&dir);
+            ctx->fs_size = ngx_de_fs_size(&dir);
             ctx->access = ngx_de_access(&dir);
             ctx->mtime = ngx_de_mtime(&dir);
 

src/core/ngx_file.h

@@ -104,6 +104,7 @@ typedef ngx_int_t (*ngx_tree_handler_pt) (ngx_tree_ctx_t *ctx, ngx_str_t *name);
 
 struct ngx_tree_ctx_s {
     off_t                      size;
+    off_t                      fs_size;
     ngx_uint_t                 access;
     time_t                     mtime;
 

src/http/ngx_http_file_cache.c

@@ -531,26 +531,19 @@ ngx_http_file_cache_exists(ngx_http_file_cache_t *cache, ngx_http_cache_t *c)
             goto done;
         }
 
-        if (fcn->exists) {
+        if (fcn->exists || fcn->uses >= c->min_uses) {
 
             c->exists = fcn->exists;
-            c->body_start = fcn->body_start;
+            if (fcn->body_start) {
+                c->body_start = fcn->body_start;
+            }
 
             rc = NGX_OK;
 
             goto done;
         }
 
-        if (fcn->uses >= c->min_uses) {
-
-            c->exists = fcn->exists;
-            c->body_start = fcn->body_start;
-
-            rc = NGX_OK;
-
-        } else {
-            rc = NGX_AGAIN;
-        }
+        rc = NGX_AGAIN;
 
         goto done;
     }
@@ -859,7 +852,7 @@ ngx_http_cache_send(ngx_http_request_t *r)
     c = r->cache;
 
     ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
-                  "http file cache send: %s", c->file.name.data);
+                   "http file cache send: %s", c->file.name.data);
 
     /* we need to allocate all before the header would be sent */
 
@@ -1328,68 +1321,27 @@ ngx_http_file_cache_manage_file(ngx_tree_ctx_t *ctx, ngx_str_t *path)
 static ngx_int_t
 ngx_http_file_cache_add_file(ngx_tree_ctx_t *ctx, ngx_str_t *name)
 {
-    u_char                        *p;
-    ngx_fd_t                       fd;
-    ngx_int_t                      n;
-    ngx_uint_t                     i;
-    ngx_file_info_t                fi;
-    ngx_http_cache_t               c;
-    ngx_http_file_cache_t         *cache;
-    ngx_http_file_cache_header_t   h;
+    u_char                 *p;
+    ngx_int_t               n;
+    ngx_uint_t              i;
+    ngx_http_cache_t        c;
+    ngx_http_file_cache_t  *cache;
 
     if (name->len < 2 * NGX_HTTP_CACHE_KEY_LEN) {
         return NGX_ERROR;
     }
 
-    ngx_memzero(&c, sizeof(ngx_http_cache_t));
-
-    fd = ngx_open_file(name->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
-
-    if (fd == NGX_INVALID_FILE) {
-        ngx_log_error(NGX_LOG_CRIT, ctx->log, ngx_errno,
-                      ngx_open_file_n " \"%s\" failed", name->data);
-        return NGX_ERROR;
-    }
-
-    c.file.fd = fd;
-    c.file.name = *name;
-    c.file.log = ctx->log;
-
-    n = ngx_read_file(&c.file, (u_char *) &h,
-                      sizeof(ngx_http_file_cache_header_t), 0);
-    if (n == NGX_ERROR) {
-        return NGX_ERROR;
-    }
-
-    if ((size_t) n < sizeof(ngx_http_file_cache_header_t)) {
+    if (ctx->size < (off_t) sizeof(ngx_http_file_cache_header_t)) {
         ngx_log_error(NGX_LOG_CRIT, ctx->log, 0,
                       "cache file \"%s\" is too small", name->data);
         return NGX_ERROR;
     }
 
+    ngx_memzero(&c, sizeof(ngx_http_cache_t));
     cache = ctx->data;
 
-    if (ngx_fd_info(fd, &fi) == NGX_FILE_ERROR) {
-        ngx_log_error(NGX_LOG_CRIT, ctx->log, ngx_errno,
-                      ngx_fd_info_n " \"%s\" failed", name->data);
-
-    } else {
-        c.uniq = ngx_file_uniq(&fi);
-        c.valid_sec = h.valid_sec;
-        c.valid_msec = h.valid_msec;
-        c.body_start = h.body_start;
-        c.length = ngx_file_size(&fi);
-        c.fs_size = (ngx_file_fs_size(&fi) + cache->bsize - 1) / cache->bsize;
-    }
-
-    if (ngx_close_file(fd) == NGX_FILE_ERROR) {
-        ngx_log_error(NGX_LOG_ALERT, ctx->log, ngx_errno,
-                      ngx_close_file_n " \"%s\" failed", name->data);
-    }
-
-    if (c.body_start == 0) {
-        return NGX_ERROR;
-    }
+    c.length = ctx->size;
+    c.fs_size = (ctx->fs_size + cache->bsize - 1) / cache->bsize;
 
     p = &name->data[name->len - 2 * NGX_HTTP_CACHE_KEY_LEN];
 
@@ -1436,14 +1388,14 @@ ngx_http_file_cache_add(ngx_http_file_cache_t *cache, ngx_http_cache_t *c)
 
         fcn->uses = 1;
         fcn->count = 0;
-        fcn->valid_msec = c->valid_msec;
+        fcn->valid_msec = 0;
         fcn->error = 0;
         fcn->exists = 1;
         fcn->updating = 0;
         fcn->deleting = 0;
-        fcn->uniq = c->uniq;
-        fcn->valid_sec = c->valid_sec;
-        fcn->body_start = c->body_start;
+        fcn->uniq = 0;
+        fcn->valid_sec = 0;
+        fcn->body_start = 0;
         fcn->fs_size = c->fs_size;
 
         cache->sh->size += c->fs_size;

src/os/unix/ngx_files.h

@@ -253,6 +253,7 @@ ngx_de_info(u_char *name, ngx_dir_t *dir)
 
 #define ngx_de_access(dir)       (((dir)->info.st_mode) & 0777)
 #define ngx_de_size(dir)         (dir)->info.st_size
+#define ngx_de_fs_size(dir)      ((dir)->info.st_blocks * 512)
 #define ngx_de_mtime(dir)        (dir)->info.st_mtime
 
 

src/os/win32/ngx_files.h

@@ -227,6 +227,7 @@ ngx_int_t ngx_de_link_info(u_char *name, ngx_dir_t *dir);
 #define ngx_de_access(dir)          0
 #define ngx_de_size(dir)                                                     \
   (((off_t) (dir)->finddata.nFileSizeHigh << 32) | (dir)->finddata.nFileSizeLow)
+#define ngx_de_fs_size(dir)         ngx_de_size(dir)
 
 /* 116444736000000000 is commented in src/os/win32/ngx_time.c */