Author: stefan2
Date: Tue Dec 30 15:05:41 2014
New Revision: 1648537
URL: http://svn.apache.org/r1648537
Log:
In FSFS, instead of locking the L1 DAG cache when handing out references
to its contents, copy the nodes into the result pool. Because DAG nodes
are large objects (~1KB typ.), copy them only if they are not already in
the result pool.
This is the core patch for the memory growth issue caused by long-living
pools inadvertently holding locks on the cache. The now unused locking
logic will be removed in later commits.
* subversion/libsvn_fs_fs/dag.h
(svn_fs_fs__dag_copy_into_pool): New wrapper around svn_fs_fs__dag_dup
that prevents unnecessary copies.
* subversion/libsvn_fs_fs/dag.c
(svn_fs_fs__dag_copy_into_pool): Implement.
* subversion/libsvn_fs_fs/tree.c
(dag_node_cache_get): Ignore the cache lock requests. Cache locking
is no longer necessary.
(make_parent_path,
open_path): Ensure that all DAG nodes in the parent_path_t structure
are allocated in the result pool.
Modified:
subversion/trunk/subversion/libsvn_fs_fs/dag.c
subversion/trunk/subversion/libsvn_fs_fs/dag.h
subversion/trunk/subversion/libsvn_fs_fs/tree.c
Modified: subversion/trunk/subversion/libsvn_fs_fs/dag.c
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/dag.c?rev=1648537&r1=1648536&r2=1648537&view=diff
==============================================================================
--- subversion/trunk/subversion/libsvn_fs_fs/dag.c (original)
+++ subversion/trunk/subversion/libsvn_fs_fs/dag.c Tue Dec 30 15:05:41 2014
@@ -1105,6 +1105,15 @@ svn_fs_fs__dag_dup(const dag_node_t *nod
return new_node;
}
+dag_node_t *
+svn_fs_fs__dag_copy_into_pool(dag_node_t *node,
+ apr_pool_t *pool)
+{
+ return (node->node_pool == pool
+ ? node
+ : svn_fs_fs__dag_dup(node, pool));
+}
+
svn_error_t *
svn_fs_fs__dag_serialize(void **data,
apr_size_t *data_len,
Modified: subversion/trunk/subversion/libsvn_fs_fs/dag.h
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/dag.h?rev=1648537&r1=1648536&r2=1648537&view=diff
==============================================================================
--- subversion/trunk/subversion/libsvn_fs_fs/dag.h (original)
+++ subversion/trunk/subversion/libsvn_fs_fs/dag.h Tue Dec 30 15:05:41 2014
@@ -80,6 +80,12 @@ dag_node_t *
svn_fs_fs__dag_dup(const dag_node_t *node,
apr_pool_t *pool);
+/* If NODE has been allocated in POOL, return NODE. Otherwise, return
+ a copy created in POOL with svn_fs_fs__dag_dup. */
+dag_node_t *
+svn_fs_fs__dag_copy_into_pool(dag_node_t *node,
+ apr_pool_t *pool);
+
/* Serialize a DAG node, except don't try to preserve the 'fs' member.
Implements svn_cache__serialize_func_t */
svn_error_t *
Modified: subversion/trunk/subversion/libsvn_fs_fs/tree.c
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/tree.c?rev=1648537&r1=1648536&r2=1648537&view=diff
==============================================================================
--- subversion/trunk/subversion/libsvn_fs_fs/tree.c (original)
+++ subversion/trunk/subversion/libsvn_fs_fs/tree.c Tue Dec 30 15:05:41 2014
@@ -532,11 +532,6 @@ dag_node_cache_get(dag_node_t **node_p,
{
node = bucket->node;
}
-
- /* if we found a node, make sure it remains valid at least as long
- as it would when allocated in POOL. */
- if (node && needs_lock_cache)
- lock_cache(ffd->dag_node_cache, pool);
}
else
{
@@ -919,7 +914,8 @@ make_parent_path(dag_node_t *node,
apr_pool_t *pool)
{
parent_path_t *parent_path = apr_pcalloc(pool, sizeof(*parent_path));
- parent_path->node = node;
+ if (node)
+ parent_path->node = svn_fs_fs__dag_copy_into_pool(node, pool);
parent_path->entry = entry;
parent_path->parent = parent;
parent_path->copy_inherit = copy_id_inherit_unknown;
@@ -1197,7 +1193,7 @@ open_path(parent_path_t **parent_path_p,
if (flags & open_path_node_only)
{
/* Shortcut: the caller only wants the final DAG node. */
- parent_path->node = child;
+ parent_path->node = svn_fs_fs__dag_copy_into_pool(child, pool);
}
else
{
