From 1521bb95a7bb3df5cb3a128085a088cb09555f8b Mon Sep 17 00:00:00 2001 From: Matthieu Patou Date: Wed, 9 May 2012 22:08:55 -0700 Subject: [PATCH] dsdb-schema: do not reload more often than schema_reload_interval Samba 4 use to try to reload the schema every time dsdb_get_schema was called (which could be 20+ time per ldb request). Now we only reload at most every xx seconds (xx being the value of dsdb:"schema_reload_interval" or 120). The timestamp of the last reloaded schema is kept in the dsdb_schema object. There is also a timestamp in the ldb_context, that is used by the LDAP server to know if it has to reload the schema after handling the request. This is used to allow that the schema will be immediately reload after a schemaUpdateNow request has been issued, the reload can't occur in the handling of the LDAP request itself because we have a transaction autostarted. --- source4/dsdb/samdb/ldb_modules/samldb.c | 3 ++ source4/dsdb/samdb/ldb_modules/schema_load.c | 39 +++++++++++++++++++- source4/dsdb/samdb/samdb.h | 1 + source4/dsdb/schema/schema.h | 1 + source4/ldap_server/ldap_backend.c | 25 ++++++++++++- 5 files changed, 65 insertions(+), 4 deletions(-) diff --git a/source4/dsdb/samdb/ldb_modules/samldb.c b/source4/dsdb/samdb/ldb_modules/samldb.c index 41c97bf32a4..7b98dd62c1f 100644 --- a/source4/dsdb/samdb/ldb_modules/samldb.c +++ b/source4/dsdb/samdb/ldb_modules/samldb.c @@ -4,6 +4,7 @@ Copyright (C) Andrew Bartlett 2005 Copyright (C) Simo Sorce 2004-2008 Copyright (C) Matthias Dieter Wallnöfer 2009-2011 + Copyright (C) Matthieu Patou 2012 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -428,6 +429,8 @@ static int samldb_add_handle_msDS_IntId(struct samldb_ctx *ac) struct ldb_context *ldb; struct ldb_result *ldb_res; struct ldb_dn *schema_dn; + struct samldb_msds_intid_persistant *msds_intid_struct; + struct dsdb_schema *schema; ldb = ldb_module_get_ctx(ac->module); schema_dn = ldb_get_schema_basedn(ldb); diff --git a/source4/dsdb/samdb/ldb_modules/schema_load.c b/source4/dsdb/samdb/ldb_modules/schema_load.c index 4c166d51ce5..f922aabba90 100644 --- a/source4/dsdb/samdb/ldb_modules/schema_load.c +++ b/source4/dsdb/samdb/ldb_modules/schema_load.c @@ -49,6 +49,10 @@ static struct dsdb_schema *dsdb_schema_refresh(struct ldb_module *module, struct struct dsdb_control_current_partition *ctrl; struct ldb_context *ldb = ldb_module_get_ctx(module); struct dsdb_schema *new_schema; + int interval; + time_t ts, lastts; + struct loadparm_context *lp_ctx = + (struct loadparm_context *)ldb_get_opaque(ldb, "loadparm"); struct schema_load_private_data *private_data = talloc_get_type(ldb_module_get_private(module), struct schema_load_private_data); if (!private_data) { @@ -61,6 +65,14 @@ static struct dsdb_schema *dsdb_schema_refresh(struct ldb_module *module, struct return schema; } + lastts = schema->last_refresh; + ts = time(NULL); + interval = lpcfg_parm_int(lp_ctx, NULL, "dsdb", "schema_reload_interval", 120); + if (lastts > (ts - interval)) { + DEBUG(11, ("Less than %d seconds since last reload, returning cached version ts = %d\n", interval, (int)lastts)); + return schema; + } + res = talloc_zero(schema, struct ldb_result); if (res == NULL) { return NULL; @@ -84,7 +96,16 @@ static struct dsdb_schema *dsdb_schema_refresh(struct ldb_module *module, struct talloc_free(res); return NULL; } - + + /* + * We update right now the last refresh timestamp so that if + * the schema partition hasn't change we don't keep on retrying. + * Otherwise if the timestamp was update only when the schema has + * actually changed (and therefor completely reloaded) we would + * continue to hit the database to get the highest USN. + */ + schema->last_refresh = ts; + ctrl = talloc(treq, struct dsdb_control_current_partition); if (!ctrl) { talloc_free(res); @@ -130,7 +151,7 @@ static struct dsdb_schema *dsdb_schema_refresh(struct ldb_module *module, struct if (ret != LDB_SUCCESS) { return schema; } - + if (is_global_schema) { dsdb_make_schema_global(ldb, new_schema); } @@ -226,6 +247,7 @@ static int dsdb_schema_from_db(struct ldb_module *module, struct ldb_dn *schema_ ret = dsdb_set_schema(ldb, (*schema)); (*schema)->refresh_in_progress = false; + (*schema)->last_refresh = time(NULL); if (ret != LDB_SUCCESS) { ldb_debug_set(ldb, LDB_DEBUG_FATAL, @@ -324,9 +346,22 @@ static int schema_load_del_transaction(struct ldb_module *module) static int schema_load_extended(struct ldb_module *module, struct ldb_request *req) { + time_t *lastts; + struct ldb_context *ldb = ldb_module_get_ctx(module); + struct dsdb_schema *schema; + if (strcmp(req->op.extended.oid, DSDB_EXTENDED_SCHEMA_UPDATE_NOW_OID) != 0) { return ldb_next_request(module, req); } + lastts = (time_t *)ldb_get_opaque(ldb, DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME); + if (!lastts) { + lastts = talloc(ldb, time_t); + } + schema = dsdb_get_schema(ldb, NULL); + /* Force a refresh */ + schema->last_refresh = 0; + *lastts = 0; + ldb_set_opaque(ldb, DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME, lastts); /* This is a no-op. We reload as soon as we can */ return ldb_module_done(req, NULL, NULL, LDB_SUCCESS); diff --git a/source4/dsdb/samdb/samdb.h b/source4/dsdb/samdb/samdb.h index 50f7bf7d13a..2a4bd355eb5 100644 --- a/source4/dsdb/samdb/samdb.h +++ b/source4/dsdb/samdb/samdb.h @@ -199,6 +199,7 @@ struct dsdb_extended_dn_store_format { bool store_extended_dn_in_ldb; }; +#define DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME "DSDB_OPAQUE_LAST_SCHEMA_UPDATE" #define DSDB_OPAQUE_PARTITION_MODULE_MSG_OPAQUE_NAME "DSDB_OPAQUE_PARTITION_MODULE_MSG" /* this takes a struct dsdb_fsmo_extended_op */ diff --git a/source4/dsdb/schema/schema.h b/source4/dsdb/schema/schema.h index b1ae76882ab..d3dd035e013 100644 --- a/source4/dsdb/schema/schema.h +++ b/source4/dsdb/schema/schema.h @@ -245,6 +245,7 @@ struct dsdb_schema { struct ldb_module *loaded_from_module; struct dsdb_schema *(*refresh_fn)(struct ldb_module *module, struct dsdb_schema *schema, bool is_global_schema); bool refresh_in_progress; + time_t last_refresh; /* an 'opaque' sequence number that the reload function may also wish to use */ uint64_t reload_seq_number; diff --git a/source4/ldap_server/ldap_backend.c b/source4/ldap_server/ldap_backend.c index afeb3500d0f..000d7e28f81 100644 --- a/source4/ldap_server/ldap_backend.c +++ b/source4/ldap_server/ldap_backend.c @@ -1162,6 +1162,9 @@ NTSTATUS ldapsrv_do_call(struct ldapsrv_call *call) { unsigned int i; struct ldap_message *msg = call->request; + struct ldb_context *samdb = call->conn->ldb; + NTSTATUS status; + time_t *lastts; /* Check for undecoded critical extensions */ for (i=0; msg->controls && msg->controls[i]; i++) { if (!msg->controls_decoded[i] && @@ -1180,9 +1183,11 @@ NTSTATUS ldapsrv_do_call(struct ldapsrv_call *call) case LDAP_TAG_SearchRequest: return ldapsrv_SearchRequest(call); case LDAP_TAG_ModifyRequest: - return ldapsrv_ModifyRequest(call); + status = ldapsrv_ModifyRequest(call); + break; case LDAP_TAG_AddRequest: - return ldapsrv_AddRequest(call); + status = ldapsrv_AddRequest(call); + break; case LDAP_TAG_DelRequest: return ldapsrv_DelRequest(call); case LDAP_TAG_ModifyDNRequest: @@ -1196,4 +1201,20 @@ NTSTATUS ldapsrv_do_call(struct ldapsrv_call *call) default: return ldapsrv_unwilling(call, LDAP_PROTOCOL_ERROR); } + + if (NT_STATUS_IS_OK(status)) { + lastts = (time_t *)ldb_get_opaque(samdb, DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME); + if (lastts && !*lastts) { + DEBUG(10, ("Schema update now was requested, fullfilling the request ts = %d\n", lastts)); + /* + * Just requesting the schema will do the trick + * as the delay for reload is experied, we will have a reload + * from the schema as expected as we are not yet in a transaction! + */ + dsdb_get_schema(samdb, NULL); + *lastts = time(NULL); + ldb_set_opaque(samdb, DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME, lastts); + } + } + return status; }