Editing C dynamic memory allocation (section)

===FreeBSD's and NetBSD's jemalloc===
Since [[FreeBSD]] 7.0 and [[NetBSD]] 5.0, the old <code>malloc</code> implementation ({{code|phkmalloc}} by [[Poul-Henning Kamp]]) was replaced by [http://jemalloc.net/ jemalloc], written by Jason Evans.  The main reason for this was a lack of scalability of {{code|phkmalloc}} in terms of multithreading.  In order to avoid lock contention, {{code|jemalloc}} uses separate "arenas" for each [[central processing unit|CPU]].  Experiments measuring number of allocations per second in multithreading application have shown that this makes it scale linearly with the number of threads, while for both phkmalloc and dlmalloc performance was inversely proportional to the number of threads.<ref>{{cite web |url=http://people.freebsd.org/~jasone/jemalloc/bsdcan2006/jemalloc.pdf |title=A Scalable Concurrent malloc(3) Implementation for FreeBSD |first=Jason |last=Evans |date=16 April 2006 |access-date=18 March 2012 }}</ref>

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