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From Ravikumar Govindarajan <>
Subject Help on MMap of SSTables
Date Tue, 04 Dec 2012 10:59:45 GMT
Our current SSTable sizes are far greater than RAM. {150 Gigs of data, 32GB
RAM}. Currently we run with mlockall and mmap_index_only options and don't
experience swapping at all.

We use wide rows and size-tiered-compaction, so a given key will definitely
be spread across multiple sstables. Will MMapping data files be detrimental
for reads, in this case?

In general, when should we opt for MMap data files and what are the factors
that need special attention when enabling the same?


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