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Posted to commits@subversion.apache.org by st...@apache.org on 2010/11/21 21:14:09 UTC
svn commit: r1037548 - in
/subversion/branches/performance/subversion/libsvn_fs_fs: caching.c fs.h
fs_fs.c id.c id.h
Author: stefan2
Date: Sun Nov 21 20:14:09 2010
New Revision: 1037548
URL: http://svn.apache.org/viewvc?rev=1037548&view=rev
Log:
Address issues from http://svn.haxx.se/dev/archive-2010-10/0499.shtml
It's not actually necessary to tag the cached revision root IDs with
"belongs to packed / non-packed rev". Use separate caches for these
cases, instead.
The reason that this works is that there can be only one transition from
non-packed to packed and that this is not reversible (see comments in
code for more details).
* subversion/libsvn_fs_fs/id.h
(svn_fs_fs__is_packed, svn_fs_fs__set_packed): drop
* subversion/libsvn_fs_fs/id.c
(id_private_t): remove is_packed member
(svn_fs_fs__id_txn_create, svn_fs_fs__id_rev_create, svn_fs_fs__id_copy,
svn_fs_fs__id_parse): remove references to that member
(svn_fs_fs__is_packed, svn_fs_fs__set_packed): drop
* subversion/libsvn_fs_fs/fs.h
(fs_fs_data_t): add separate cache for packed revision root IDs
* subversion/libsvn_fs_fs/fs_fs.c
(svn_fs_fs__rev_get_root): access right ID cache; drop the ID modification
* subversion/libsvn_fs_fs/caching.c
(svn_fs_fs__initialize_caches): initialize new cache
Modified:
subversion/branches/performance/subversion/libsvn_fs_fs/caching.c
subversion/branches/performance/subversion/libsvn_fs_fs/fs.h
subversion/branches/performance/subversion/libsvn_fs_fs/fs_fs.c
subversion/branches/performance/subversion/libsvn_fs_fs/id.c
subversion/branches/performance/subversion/libsvn_fs_fs/id.h
Modified: subversion/branches/performance/subversion/libsvn_fs_fs/caching.c
URL: http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/caching.c?rev=1037548&r1=1037547&r2=1037548&view=diff
==============================================================================
--- subversion/branches/performance/subversion/libsvn_fs_fs/caching.c (original)
+++ subversion/branches/performance/subversion/libsvn_fs_fs/caching.c Sun Nov 21 20:14:09 2010
@@ -115,32 +115,53 @@ svn_fs_fs__initialize_caches(svn_fs_t *f
close_unused_file_handles,
apr_pool_cleanup_null);
- /* Make the cache for revision roots. For the vast majority of
- * commands, this is only going to contain a few entries (svnadmin
- * dump/verify is an exception here), so to reduce overhead let's
- * try to keep it to just one page. I estimate each entry has about
- * 72 bytes of overhead (svn_revnum_t key, svn_fs_id_t +
+ /* Make the caches for non-packed and packed revision roots. For the
+ * vastmajority of commands, this is only going to contain a few entries
+ * (svnadmin dump/verify is an exception here), so to reduce overhead
+ * let's try to keep it to just one page. I estimate each entry has
+ * about 72 bytes of overhead (svn_revnum_t key, svn_fs_id_t +
* id_private_t + 3 strings for value, and the cache_entry); the
* default pool size is 8192, so about a hundred should fit
* comfortably. */
if (svn_fs__get_global_membuffer_cache())
- SVN_ERR(svn_cache__create_membuffer_cache(&(ffd->rev_root_id_cache),
- svn_fs__get_global_membuffer_cache(),
- svn_fs_fs__serialize_id,
- svn_fs_fs__deserialize_id,
- sizeof(svn_revnum_t),
- apr_pstrcat(pool, prefix, "RRI",
+ {
+ SVN_ERR(svn_cache__create_membuffer_cache(&(ffd->rev_root_id_cache),
+ svn_fs__get_global_membuffer_cache(),
+ svn_fs_fs__serialize_id,
+ svn_fs_fs__deserialize_id,
+ sizeof(svn_revnum_t),
+ apr_pstrcat(pool, prefix, "RRI",
+ (char *)NULL),
+ fs->pool));
+ SVN_ERR(svn_cache__create_membuffer_cache(&(ffd->packed_rev_root_id_cache),
+ svn_fs__get_global_membuffer_cache(),
+ svn_fs_fs__serialize_id,
+ svn_fs_fs__deserialize_id,
+ sizeof(svn_revnum_t),
+ apr_pstrcat(pool, prefix, "PRRI",
(char *)NULL),
- fs->pool));
+ fs->pool));
+ }
else
- SVN_ERR(svn_cache__create_inprocess(&(ffd->rev_root_id_cache),
- svn_fs_fs__serialize_id,
- svn_fs_fs__deserialize_id,
- sizeof(svn_revnum_t),
- 1, 100, FALSE, fs->pool));
+ {
+ SVN_ERR(svn_cache__create_inprocess(&(ffd->rev_root_id_cache),
+ svn_fs_fs__serialize_id,
+ svn_fs_fs__deserialize_id,
+ sizeof(svn_revnum_t),
+ 1, 100, FALSE, fs->pool));
+ SVN_ERR(svn_cache__create_inprocess(&(ffd->packed_rev_root_id_cache),
+ svn_fs_fs__serialize_id,
+ svn_fs_fs__deserialize_id,
+ sizeof(svn_revnum_t),
+ 1, 100, FALSE, fs->pool));
+ }
if (! no_handler)
- SVN_ERR(svn_cache__set_error_handler(ffd->rev_root_id_cache,
- warn_on_cache_errors, fs, pool));
+ {
+ SVN_ERR(svn_cache__set_error_handler(ffd->rev_root_id_cache,
+ warn_on_cache_errors, fs, pool));
+ SVN_ERR(svn_cache__set_error_handler(ffd->packed_rev_root_id_cache,
+ warn_on_cache_errors, fs, pool));
+ }
/* Rough estimate: revision DAG nodes have size around 320 bytes, so
Modified: subversion/branches/performance/subversion/libsvn_fs_fs/fs.h
URL: http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/fs.h?rev=1037548&r1=1037547&r2=1037548&view=diff
==============================================================================
--- subversion/branches/performance/subversion/libsvn_fs_fs/fs.h (original)
+++ subversion/branches/performance/subversion/libsvn_fs_fs/fs.h Sun Nov 21 20:14:09 2010
@@ -226,9 +226,15 @@ typedef struct
multiple svn_fs_t's for the same filesystem.) */
/* A cache of revision root IDs, mapping from (svn_revnum_t *) to
- (svn_fs_id_t *). (Not threadsafe.) */
+ (svn_fs_id_t *). Some of the IDs may belong to non-packed revs
+ but these will never be read. This is guaranteed by the fact
+ that the transition from non-packed to packed is irreversable. */
svn_cache__t *rev_root_id_cache;
+ /* Similar to @ref rev_root_id_cache but all IDs are guaranteed
+ to belong to packed revisions. */
+ svn_cache__t *packed_rev_root_id_cache;
+
/* DAG node cache for immutable nodes */
svn_cache__t *rev_node_cache;
Modified: subversion/branches/performance/subversion/libsvn_fs_fs/fs_fs.c
URL: http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/fs_fs.c?rev=1037548&r1=1037547&r2=1037548&view=diff
==============================================================================
--- subversion/branches/performance/subversion/libsvn_fs_fs/fs_fs.c (original)
+++ subversion/branches/performance/subversion/libsvn_fs_fs/fs_fs.c Sun Nov 21 20:14:09 2010
@@ -2974,17 +2974,23 @@ svn_fs_fs__rev_get_root(svn_fs_id_t **ro
svn_file_handle_cache__handle_t *revision_file;
apr_file_t *apr_rev_file;
apr_off_t root_offset;
+ svn_cache__t *cache = NULL;
svn_fs_id_t *root_id = NULL;
svn_boolean_t is_cached;
- svn_tristate_t is_packed;
SVN_ERR(ensure_revision_exists(fs, rev, pool));
+ /* Try to find the ID in our caches. Once we tried is_packed_rev
+ returned true, we will never try to use the cache for non-packed
+ revs again. Also, if we find the entry in the cache, this
+ function cannot be racy because we don't need to access the file. */
+ cache = is_packed_rev(fs, rev)
+ ? ffd->packed_rev_root_id_cache
+ : ffd->rev_root_id_cache;
SVN_ERR(svn_cache__get((void **) root_id_p, &is_cached,
- ffd->rev_root_id_cache, &rev, pool));
+ cache, &rev, pool));
- is_packed = is_packed_rev(fs, rev) ? svn_tristate_true : svn_tristate_false;
- if (is_cached && is_packed == svn_fs_fs__is_packed(*root_id_p))
+ if (is_cached)
return SVN_NO_ERROR;
/* we don't care about the file pointer position */
@@ -2998,13 +3004,13 @@ svn_fs_fs__rev_get_root(svn_fs_id_t **ro
SVN_ERR(get_fs_id_at_offset(&root_id, apr_rev_file, fs, rev, root_offset,
pool));
- svn_fs_fs__set_packed(root_id, is_packed_rev(fs, rev)
- ? svn_tristate_true
- : svn_tristate_false);
SVN_ERR(svn_file_handle_cache__close(revision_file));
- SVN_ERR(svn_cache__set(ffd->rev_root_id_cache, &rev, root_id, pool));
+ /* At this point, the revision might have already gotten packed
+ but cache is still the one for non-packed IDs. In that case,
+ it will never be looked up here, again. So, we are safe. */
+ SVN_ERR(svn_cache__set(cache, &rev, root_id, pool));
*root_id_p = root_id;
Modified: subversion/branches/performance/subversion/libsvn_fs_fs/id.c
URL: http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/id.c?rev=1037548&r1=1037547&r2=1037548&view=diff
==============================================================================
--- subversion/branches/performance/subversion/libsvn_fs_fs/id.c (original)
+++ subversion/branches/performance/subversion/libsvn_fs_fs/id.c Sun Nov 21 20:14:09 2010
@@ -34,7 +34,6 @@ typedef struct {
const char *txn_id;
svn_revnum_t rev;
apr_off_t offset;
- svn_tristate_t is_packed;
} id_private_t;
@@ -85,24 +84,6 @@ svn_fs_fs__id_offset(const svn_fs_id_t *
}
-svn_tristate_t
-svn_fs_fs__is_packed(const svn_fs_id_t *id)
-{
- id_private_t *pvt = id->fsap_data;
-
- return pvt->is_packed;
-}
-
-void
-svn_fs_fs__set_packed(const svn_fs_id_t *id,
- svn_tristate_t is_packed)
-{
- id_private_t *pvt = id->fsap_data;
-
- pvt->is_packed = is_packed;
-}
-
-
svn_string_t *
svn_fs_fs__id_unparse(const svn_fs_id_t *id,
apr_pool_t *pool)
@@ -206,7 +187,6 @@ svn_fs_fs__id_txn_create(const char *nod
pvt->txn_id = apr_pstrdup(pool, txn_id);
pvt->rev = SVN_INVALID_REVNUM;
pvt->offset = -1;
- pvt->is_packed = svn_tristate_unknown;
id->vtable = &id_vtable;
id->fsap_data = pvt;
@@ -229,7 +209,6 @@ svn_fs_fs__id_rev_create(const char *nod
pvt->txn_id = NULL;
pvt->rev = rev;
pvt->offset = offset;
- pvt->is_packed = svn_tristate_unknown;
id->vtable = &id_vtable;
id->fsap_data = pvt;
@@ -249,7 +228,6 @@ svn_fs_fs__id_copy(const svn_fs_id_t *id
new_pvt->txn_id = pvt->txn_id ? apr_pstrdup(pool, pvt->txn_id) : NULL;
new_pvt->rev = pvt->rev;
new_pvt->offset = pvt->offset;
- new_pvt->is_packed = pvt->is_packed;
new_id->vtable = &id_vtable;
new_id->fsap_data = new_pvt;
@@ -321,7 +299,6 @@ svn_fs_fs__id_parse(const char *data,
return NULL;
}
pvt->offset = (apr_off_t)val;
- pvt->is_packed = svn_tristate_unknown;
}
else if (str[0] == 't')
{
@@ -329,7 +306,6 @@ svn_fs_fs__id_parse(const char *data,
pvt->txn_id = str + 1;
pvt->rev = SVN_INVALID_REVNUM;
pvt->offset = -1;
- pvt->is_packed = svn_tristate_unknown;
}
else
return NULL;
Modified: subversion/branches/performance/subversion/libsvn_fs_fs/id.h
URL: http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/id.h?rev=1037548&r1=1037547&r2=1037548&view=diff
==============================================================================
--- subversion/branches/performance/subversion/libsvn_fs_fs/id.h (original)
+++ subversion/branches/performance/subversion/libsvn_fs_fs/id.h Sun Nov 21 20:14:09 2010
@@ -49,12 +49,6 @@ svn_revnum_t svn_fs_fs__id_rev(const svn
ID. */
apr_off_t svn_fs_fs__id_offset(const svn_fs_id_t *id);
-/* Access the "is_packed" flag of the ID. */
-svn_tristate_t svn_fs_fs__is_packed(const svn_fs_id_t *id);
-
-/* Set the "is_packed" flag of the ID. */
-void svn_fs_fs__set_packed(const svn_fs_id_t *id, svn_tristate_t is_packed);
-
/* Convert ID into string form, allocated in POOL. */
svn_string_t *svn_fs_fs__id_unparse(const svn_fs_id_t *id,
apr_pool_t *pool);