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Re: BUG #15396: initdb emits wrong comment for range foreffective_io_concurrency - Mailing list pgsql-bugs

From James Robinson
Subject Re: BUG #15396: initdb emits wrong comment for range foreffective_io_concurrency
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Msg-id FC4EF41B-8D7D-44AD-87B3-B6A8FFAB0885@jlr-photo.com
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In response to Re: BUG #15396: initdb emits wrong comment for range for effective_io_concurrency  (Sergei Kornilov <sk@zsrv.org>)
Responses Re: BUG #15396: initdb emits wrong comment for range for effective_io_concurrency
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On Sep 23, 2018, at 2:27 PM, Sergei Kornilov <sk@zsrv.org> wrote:

Hello

effective_io_concurrency can not be set is your system does not support USE_POSIX_FADVISE. In this case only allowed value for effective_io_concurrency is zero.
As far i know mac os does not support posix_fadvise.

Also this is documented behavior https://www.postgresql.org/docs/11/static/runtime-config-resource.html
Asynchronous I/O depends on an effective posix_fadvise function, which some operating systems lack. If the function is not present then setting this parameter to anything but zero will result in an error.

regards, Sergei

Thanks Sergei,

Possibilities of augmenting either the initdb template comments according to if USE_POSIX_FADVISE or not, or perhaps the runtime error (probably harder).

In any event, I agree not a PG11 beta issue. Perhaps I'll craft a pithy patch against HEAD sometime in the future.

James

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