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Doc: remove claim that hash index creation depends on effective_cache_size.
This text was added by commitff213239c
, and not long thereafter obsoleted by commit4adc2f72a
(which made the test depend on NBuffers instead); but nobody noticed the need for an update. Commit9563d5b5e
adds some further dependency on maintenance_work_mem, but the existing verbiage seems to cover that with about as much precision as we really want here. Let's just take it all out rather than leaving ourselves open to more errors of omission in future. (That solution makes this change back-patchable, too.) Noted by Peter Geoghegan. Discussion: <CAM3SWZRVANbj9GA9j40fAwheQCZQtSwqTN1GBTVwRrRbmSf7cg@mail.gmail.com>
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@ -568,16 +568,7 @@ Indexes:
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dependent on the setting of <xref linkend="guc-maintenance-work-mem">.
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Larger values will reduce the time needed for index creation, so long
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as you don't make it larger than the amount of memory really available,
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which would drive the machine into swapping. For hash indexes, the
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value of <xref linkend="guc-effective-cache-size"> is also relevant to
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index creation time: <productname>PostgreSQL</productname> will use one
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of two different hash index creation methods depending on whether the
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estimated index size is more or less than <varname>effective_cache_size</>.
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For best results, make sure that this parameter is also set to something
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reflective of available memory, and be careful that the sum of
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<varname>maintenance_work_mem</> and <varname>effective_cache_size</> is
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less than the machine's RAM less whatever space is needed by other
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programs.
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which would drive the machine into swapping.
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</para>
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<para>
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