Skip to content

Arrange the cache logic for vhost and context. #619

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
jfclere merged 1 commit into from
Aug 18, 2022
Merged

Arrange the cache logic for vhost and context. #619

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
29 changes: 28 additions & 1 deletion native/mod_proxy_cluster/mod_proxy_cluster.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -159,8 +159,9 @@ struct node_context
typedef struct node_context node_context;

/* Create static table references we can look back to instead of fetching each request */
static apr_time_t cache_share_for = apr_time_from_sec(0); /* cache the shared memory in the process for n seconds */
static apr_time_t cache_share_for = apr_time_from_sec(0); /* cache the node shared memory in the process for n seconds */
static apr_time_t last_cached = 0;
static apr_time_t vhost_context_last_cached = 0; /* cache the context and virtualhost */
static apr_pool_t *cached_pool = NULL;
static proxy_vhost_table *cached_vhost_table = NULL;
static proxy_context_table *cached_context_table = NULL;
Expand Down Expand Up @@ -2412,8 +2413,10 @@ static void * APR_THREAD_FUNC proxy_cluster_watchdog_func(apr_thread_t *thd, voi
/* time to refresh or create */
apr_time_t now = apr_time_now();
if (now >= last_cached+cache_share_for) {
/* we are good to lock here, because there is only this thread updating last_cached */
apr_thread_mutex_lock(lock);
last_cached = now;
vhost_context_last_cached = now; /* vhost_context_last_cached is retested in proxy_cluster_trans */
if (cached_pool) {
/* we need to update the cache */
update_vhost_table_cached(cached_vhost_table);
Expand All @@ -2430,6 +2433,9 @@ static void * APR_THREAD_FUNC proxy_cluster_watchdog_func(apr_thread_t *thd, voi
"cached_pool: should have been created in proxy_cluster_child_init!");
}
apr_thread_mutex_unlock(lock);
} else {
/* we are using cached values */
last = 0;
}
node_table = cached_node_table;
} else {
Expand Down Expand Up @@ -2531,6 +2537,8 @@ static void proxy_cluster_child_init(apr_pool_t *p, server_rec *s)
cached_balancer_table = read_balancer_table(cached_pool, 1);
cached_node_table = read_node_table(cached_pool, 1);
node_table = cached_node_table;
last_cached = apr_time_now();
vhost_context_last_cached = last_cached;
} else {
node_table = read_node_table(pool, 0);
}
Expand Down Expand Up @@ -2861,6 +2869,25 @@ static int proxy_cluster_trans(request_rec *r)
if (cache_share_for) {
ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_DEBUG, 0, r->server,
"proxy_cluster_trans with cache");
/*
* test the r->request_time for context and vhost modifications
* the watchdog thread only takes care of the node updates,
* update in context/virtualhost are not notified by node_storage->worker_nodes_need_update
*/
if (r->request_time > vhost_context_last_cached+cache_share_for) {
apr_thread_mutex_lock(lock);
/* we have the lock, another might have changed vhost_context_last_cached */
if (r->request_time > vhost_context_last_cached+cache_share_for) {
ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_DEBUG, 0, r->server,
"proxy_cluster_trans with cache: update vhost and context");
if (cached_vhost_table != NULL)
update_vhost_table_cached(cached_vhost_table);
if (cached_context_table != NULL)
update_context_table_cached(cached_context_table);
vhost_context_last_cached = r->request_time;
}
apr_thread_mutex_unlock(lock);
}
vhost_table = cached_vhost_table;
context_table = cached_context_table;
balancer_table = cached_balancer_table;
Expand Down