| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| /*------------------------------------------------------------------------- |
| * |
| * cdbrelsize.h |
| * |
| * Get the max size of the relation across the segDBs |
| * |
| *------------------------------------------------------------------------- |
| */ |
| #include "postgres.h" |
| |
| #include <math.h> |
| |
| #include "utils/lsyscache.h" |
| #include "utils/relcache.h" |
| #include "utils/syscache.h" |
| #include "catalog/catalog.h" |
| #include "cdb/cdbvars.h" |
| #include "miscadmin.h" |
| #include "cdb/cdbdisp.h" |
| #include "gp-libpq-fe.h" |
| #include "lib/stringinfo.h" |
| #include "utils/int8.h" |
| #include "utils/lsyscache.h" |
| #include "utils/builtins.h" |
| |
| #include "cdb/cdbrelsize.h" |
| |
| #define relsize_cache_size 100 |
| |
| struct relsize_cache_entry |
| { |
| Oid relOid; |
| int64 size; |
| }; |
| |
| static struct relsize_cache_entry relsize_cache[relsize_cache_size] = { {0,0} }; |
| |
| static int last_cache_entry = -1; /* -1 for cache not initialized yet */ |
| |
| /* |
| * in dbsize.c |
| */ |
| extern int64 calculate_relation_size(Relation rel); |
| |
| void clear_relsize_cache(void) |
| { |
| int i; |
| for (i=0; i < relsize_cache_size; i++) |
| { |
| relsize_cache[i].relOid = InvalidOid; |
| relsize_cache[i].size = 0; |
| } |
| last_cache_entry = -1; |
| } |
| |
| int64 cdbRelSize(Relation rel) |
| { |
| int64 size = 0; |
| int i; |
| |
| if (last_cache_entry >= 0) |
| { |
| for (i=0; i < relsize_cache_size; i++) |
| { |
| if (relsize_cache[i].relOid == RelationGetRelid(rel)) |
| return relsize_cache[i].size; |
| } |
| } |
| |
| size = calculate_relation_size(rel); |
| |
| if (size >= 0) /* Cache the size even if it is zero, as table might be empty */ |
| { |
| if (last_cache_entry < 0) |
| last_cache_entry = 0; |
| |
| relsize_cache[last_cache_entry].relOid = RelationGetRelid(rel); |
| relsize_cache[last_cache_entry].size = size; |
| last_cache_entry = (last_cache_entry+1) % relsize_cache_size; |
| } |
| |
| return size; |
| } |