dbcc showcontig and pageio latch waits | SQL Server Performance Forums

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dbcc showcontig and pageio latch waits

Anyone know why running dbcc showcontig would result in excessive pageio latch waits?
show contig has to read from the physical file, everything. so it is a disk intensive activity and the more heavily fragmented your data, the more reading it will need to do, and usually the more waiting. chris
DBCC SHOWCONTIG statement traverses the page chain at the leaf level of the specified index when index_id is specified. If only table_id is specified, or if index_id is 0, the data pages of the specified table are scanned. Because these modifications are not usually distributed equally among the rows of the table, the fullness of each page can vary over time. For queries that scan part or all of a table, such table fragmentation can cause additional page reads, which hinders parallel scanning of data.
Satya SKJ
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