Archives: January 2012
Prefetch is a mechanism with which SQL Server can fire up many I/O requests in parallel for Nested Loop join.
The SAN administrator says your data volume has a throughput capacity of 400MB/sec. But your long running query is waiting for I/Os (PAGEIOLATCH_SH) and Windows Performance Monitor shows your data… Read more
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Posted in Ramesh Meyyappan’s SQL Server Performance Tuning Blog on 7 January 2012