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| author | Michael Cahill <michael.cahill@wiredtiger.com> | 2012-04-10 13:29:19 +1000 |
|---|---|---|
| committer | Michael Cahill <michael.cahill@wiredtiger.com> | 2012-04-10 13:29:19 +1000 |
| commit | 35bfd2fd336cda5298020e97ec00ef9992ce40a1 (patch) | |
| tree | ec2e6ee70cbfac10577a5669d6e2aad7dad1c14a | |
| parent | 30fa005a8fd3ec8afcd4d37c45f89916e4e52504 (diff) | |
| download | mongo-35bfd2fd336cda5298020e97ec00ef9992ce40a1.tar.gz | |
Create the schema table as part of creating the environment so that application threads don't race trying to create it later.
This is not a complete solution: threads may still race creating other files or
schema objects, but this fixes the most common "thundering herd" case.
refs #191
| -rw-r--r-- | src/conn/conn_api.c | 14 | ||||
| -rw-r--r-- | src/include/extern.h | 1 | ||||
| -rw-r--r-- | src/schema/schema_table.c | 8 |
3 files changed, 19 insertions, 4 deletions
diff --git a/src/conn/conn_api.c b/src/conn/conn_api.c index ad3ef8d7e84..e6e9e5eaa31 100644 --- a/src/conn/conn_api.c +++ b/src/conn/conn_api.c @@ -374,6 +374,7 @@ wiredtiger_open(const char *home, WT_EVENT_HANDLER *event_handler, WT_CONFIG_ITEM cval, skey, sval; WT_CONNECTION_IMPL *conn; WT_ITEM *cbuf, expath, exconfig; + WT_SESSION *wt_session; WT_SESSION_IMPL *session; int ret; const char *cfg[] = @@ -512,6 +513,19 @@ wiredtiger_open(const char *home, WT_EVENT_HANDLER *event_handler, conn = NULL; WT_ERR(ret); } + + /* + * If this is a new database, create the schema file. This avoids + * application threads racing to create it later. We need a real + * session handle for this: open one. + */ + if (conn->is_new) { + WT_ERR(conn->iface.open_session(&conn->iface, + NULL, NULL, &wt_session)); + WT_TRET(__wt_open_schema_table((WT_SESSION_IMPL *)wt_session)); + WT_TRET(wt_session->close(wt_session, NULL)); + WT_ERR(ret); + } STATIC_ASSERT(offsetof(WT_CONNECTION_IMPL, iface) == 0); *wt_connp = &conn->iface; diff --git a/src/include/extern.h b/src/include/extern.h index 652618bcd87..c4dc303a0b2 100644 --- a/src/include/extern.h +++ b/src/include/extern.h @@ -711,6 +711,7 @@ extern int __wt_schema_rename(WT_SESSION_IMPL *session, const char *uri, const char *newuri, const char *cfg[]); +extern int __wt_open_schema_table(WT_SESSION_IMPL *session); extern int __wt_schema_table_cursor( WT_SESSION_IMPL *session, const char *config, WT_CURSOR **cursorp); diff --git a/src/schema/schema_table.c b/src/schema/schema_table.c index d6404e3c9fc..41ba9055f68 100644 --- a/src/schema/schema_table.c +++ b/src/schema/schema_table.c @@ -10,11 +10,11 @@ static const char *schematab_config = "key_format=S,value_format=S"; /* - * __open_schema_table -- + * __wt_open_schema_table -- * Opens the schema table, sets session->schematab. */ -static inline int -__open_schema_table(WT_SESSION_IMPL *session) +int +__wt_open_schema_table(WT_SESSION_IMPL *session) { const char *cfg[] = API_CONF_DEFAULTS(file, meta, schematab_config); const char *schemaconf; @@ -54,7 +54,7 @@ __wt_schema_table_cursor( { const char *cfg[] = API_CONF_DEFAULTS(session, open_cursor, config); - WT_RET(__open_schema_table(session)); + WT_RET(__wt_open_schema_table(session)); session->btree = session->schematab; return (__wt_curfile_create(session, NULL, cfg, cursorp)); } |