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you can do this kind of persistence with an immutable data structure without forking How? huge pages help to reduce memory latency Yup, but this is about _tr

by seiji 12y ago

you can do this kind of persistence with an immutable data structure without forking How? huge pages help to reduce memory latency Yup, but this is about _transparent_ huge pages which break databases all over the place: https://blogs.oracle.com/linux/entry/performance_issues_with_transparent_huge https://blogs.oracle.com/linux/entry/performance_issues_with... and http://dev.nuodb.com/techblog/linux-transparent-huge-pages-jemalloc-and-nuodb http://dev.nuodb.com/techblog/linux-transparent-huge-pages-j... and http://scn.sap.com/people/markmumy/blog/2014/05/22/sap-iq-and-linux-hugepagestransparent-hugepages http://scn.sap.com/people/markmumy/blog/2014/05/22/sap-iq-an... and http://www.percona.com/blog/2014/07/23/why-tokudb-hates-transparent-hugepages/ http://www.percona.com/blog/2014/07/23/why-tokudb-hates-tran... and (a dozen more including varnish, mongo, hadoop, ...)

Ono-Sendai 12y ago
If you have a pointer to an immutable data structure, you know it won't change, so you can write it out to disk at your leisure.
- justincormack 12y ago
  But the immutable data structure is not that much different from the copy-on-write pages the kernel gives you, likely to involve the same amount of copying. And disk IO is blocking so you need at least a thread, so it is a natural strategy.