On Sun, Jun 10, 2012 at 11:41 PM, Amit Kapila <amit.kapila@huawei.com> wrote:
>>>Uh... no. The whole point of doing things in shared buffers is that
>>>you don't have to write and fsync the buffers immediately. Instead,
>>>buffer evicting handles that stuff for you.
>
> So you mean to say that there exists operations where Xlog is not required
> even though it marks the buffer as dirty for later eviction.
Correct.
>>>I don't see why it's any different from log_newpage() in that regard.
>>>That data is initialized before being written, as well, but someone
>>>contemplated the possible need to write a page of all zeros.
>
> The comment above the code indicates that "the page is uninitialized".
> Does the code consider page with all zero's as uninitialized or the comment
> is not
> appropriate.
Yes, all zeroes = uninitialized.
--
Robert Haas
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