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Re: Use pg_pwritev_with_retry() instead of write() in dir_open_for_write() to avoid partial writes? - Mailing list pgsql-hackers

From Andres Freund
Subject Re: Use pg_pwritev_with_retry() instead of write() in dir_open_for_write() to avoid partial writes?
Date
Msg-id 20230215004607.y5o2c3npd3d5f7dt@awork3.anarazel.de
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In response to Re: Use pg_pwritev_with_retry() instead of write() in dir_open_for_write() to avoid partial writes?  (Michael Paquier <michael@paquier.xyz>)
Responses Re: Use pg_pwritev_with_retry() instead of write() in dir_open_for_write() to avoid partial writes?  (Michael Paquier <michael@paquier.xyz>)
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Hi,

On 2023-02-14 16:06:24 +0900, Michael Paquier wrote:
> On Mon, Feb 13, 2023 at 05:10:56PM -0800, Andres Freund wrote:
> > I just tried to use pg_pwrite_zeros - and couldn't because it doesn't have an
> > offset parameter.  Huh, what lead to the function being so constrained?
> 
> Its current set of uses cases, where we only use it now to initialize
> with zeros with WAL segments.  If you have a case that plans to use
> that stuff with an offset, no problem with me.

Then it really shouldn't have been named pg_pwrite_zeros(). The point of the
p{write,read}{,v} family of functions is to be able to specify the offset to
read/write at. I assume the p is for position, but I'm not sure.

Greetings,

Andres Freund

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