Réindexer la base de données WSUS
Les performances des déploiements WSUS volumineux se dégradent au fil du temps si la base de données WSUS n’est pas gérée correctement. Le script T-SQL de cet article peut être exécuté par les administrateurs SQL Server pour réindexer et défragmenter des bases de données WSUS. Il ne doit pas être utilisé sur les bases de données WSUS 2.0.
Script T-SQL
Ce script effectue des tâches de maintenance de base sur SUSDB :
- Identifie les index fragmentés et les défragmente. Pour certaines tables, un facteur de remplissage est défini pour améliorer les performances d’insertion.
- Met à jour les statistiques de table potentiellement obsolètes.
USE SUSDB;
GO
SET NOCOUNT ON;
-- Rebuild or reorganize indexes based on their fragmentation levels
DECLARE @work_to_do TABLE (
objectid int
, indexid int
, pagedensity float
, fragmentation float
, numrows int
)
DECLARE @objectid int;
DECLARE @indexid int;
DECLARE @schemaname nvarchar(130);
DECLARE @objectname nvarchar(130);
DECLARE @indexname nvarchar(130);
DECLARE @numrows int
DECLARE @density float;
DECLARE @fragmentation float;
DECLARE @command nvarchar(4000);
DECLARE @fillfactorset bit
DECLARE @numpages int
-- Select indexes that need to be defragmented based on the following
-- * Page density is low
-- * External fragmentation is high in relation to index size
PRINT 'Estimating fragmentation: Begin. ' + convert(nvarchar, getdate(), 121)
INSERT @work_to_do
SELECT
f.object_id
, index_id
, avg_page_space_used_in_percent
, avg_fragmentation_in_percent
, record_count
FROM
sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL , NULL, 'SAMPLED') AS f
WHERE
(f.avg_page_space_used_in_percent < 85.0 and f.avg_page_space_used_in_percent/100.0 * page_count < page_count - 1)
or (f.page_count > 50 and f.avg_fragmentation_in_percent > 15.0)
or (f.page_count > 10 and f.avg_fragmentation_in_percent > 80.0)
PRINT 'Number of indexes to rebuild: ' + cast(@@ROWCOUNT as nvarchar(20))
PRINT 'Estimating fragmentation: End. ' + convert(nvarchar, getdate(), 121)
SELECT @numpages = sum(ps.used_page_count)
FROM
@work_to_do AS fi
INNER JOIN sys.indexes AS i ON fi.objectid = i.object_id and fi.indexid = i.index_id
INNER JOIN sys.dm_db_partition_stats AS ps on i.object_id = ps.object_id and i.index_id = ps.index_id
-- Declare the cursor for the list of indexes to be processed.
DECLARE curIndexes CURSOR FOR SELECT * FROM @work_to_do
-- Open the cursor.
OPEN curIndexes
-- Loop through the indexes
WHILE (1=1)
BEGIN
FETCH NEXT FROM curIndexes
INTO @objectid, @indexid, @density, @fragmentation, @numrows;
IF @@FETCH_STATUS < 0 BREAK;
SELECT
@objectname = QUOTENAME(o.name)
, @schemaname = QUOTENAME(s.name)
FROM
sys.objects AS o
INNER JOIN sys.schemas as s ON s.schema_id = o.schema_id
WHERE
o.object_id = @objectid;
SELECT
@indexname = QUOTENAME(name)
, @fillfactorset = CASE fill_factor WHEN 0 THEN 0 ELSE 1 END
FROM
sys.indexes
WHERE
object_id = @objectid AND index_id = @indexid;
IF ((@density BETWEEN 75.0 AND 85.0) AND @fillfactorset = 1) OR (@fragmentation < 30.0)
SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REORGANIZE';
ELSE IF @numrows >= 5000 AND @fillfactorset = 0
SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REBUILD WITH (FILLFACTOR = 90)';
ELSE
SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REBUILD';
PRINT convert(nvarchar, getdate(), 121) + N' Executing: ' + @command;
EXEC (@command);
PRINT convert(nvarchar, getdate(), 121) + N' Done.';
END
-- Close and deallocate the cursor.
CLOSE curIndexes;
DEALLOCATE curIndexes;
IF EXISTS (SELECT * FROM @work_to_do)
BEGIN
PRINT 'Estimated number of pages in fragmented indexes: ' + cast(@numpages as nvarchar(20))
SELECT @numpages = @numpages - sum(ps.used_page_count)
FROM
@work_to_do AS fi
INNER JOIN sys.indexes AS i ON fi.objectid = i.object_id and fi.indexid = i.index_id
INNER JOIN sys.dm_db_partition_stats AS ps on i.object_id = ps.object_id and i.index_id = ps.index_id
PRINT 'Estimated number of pages freed: ' + cast(@numpages as nvarchar(20))
END
GO
--Update all statistics
PRINT 'Updating all statistics.' + convert(nvarchar, getdate(), 121)
EXEC sp_updatestats
PRINT 'Done updating statistics.' + convert(nvarchar, getdate(), 121)
GO