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Home -> Community -> Usenet -> c.d.o.server -> Re: how to place a table in memory
the point was, if the table is being accessed via a table scan, those
blocks are placed at the cold end of the LRU. Each time that table is
scanned, almost all the blocks are going to be read from physical IOs.
Actually, if there are blocks that are cached, they will slow down
reading the table via a full table scan, as such blocks will cause less
than full extents to be read. setting the table to "cache" and
assigning it to the keep buffer pool was simply to make the resource
usage of the table scans as small as possible. temporarily. eventually,
the code was fixed, the table set back to the default pool, and the
table was set to nocache.
duct tape it was.
it was not a fix of the problem, it reduced the impact of the problem
on the storage subsystem. It placed a stress on memory bandwidth.
It was not a fix.
hope that makes it more clear.
-bdbafh Received on Fri Feb 11 2005 - 16:06:58 CST