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[[!tag open_issue_hurd]]

  * Hurd libihash

      * old

      * new

  * hurd-l4 libhurd-ihash


# Open Issues

  * [[viengoos libhurd-ihash|microkernel/viengoos/projects/new_hash_function]]

    IRC, freenode, #hurd, 2008/2009

        <neal> so, we need a new ihash implementation
        <neal> marcusb: When 80% full, the collision rate is very high.
        <neal> marcusb: I tested using 512mb / 4096 entries
        <neal> marcusb: Changing the load factor to 30% resulted in my program
          running more than an order of magnitude faster.
        <marcusb> yeah, it shouldn't get so full
        <marcusb> don't we do an exponential back-off in the array size?
        <marcusb> of course it's clear we can do much better
        <marcusb> the ihash algo is very simple
        <marcusb> I'm not even sure it makes much sense to have a generic
          library

  * [[community/gsoc/project_ideas/object_lookups]]


# Alternatives?

  * glibc

      * include/inline-hashtab.h

      * locale/programs/simple-hash.h

      * misc/hsearch_r.c

      * NNS; cf. f46f0abfee5a2b34451708f2462a1c3b1701facd

  * libstdc++: `unordered_map`, `tr1/unordered_map`, `ext/hash_map`

  * libiberty: `hashtab.c`

  * <http://cmph.sourceforge.net/>

  * <http://libhashish.sourceforge.net/>

  * <http://www.azillionmonkeys.com/qed/hash.html>

  * CCAN's htable, idtree