Re: win32 performance - fsync question

Magnus Hagander wrote:


>> Magnus Hagander wrote:
>>> > Magnus prepared a trivial patch which added the O_SYNC flag
>>> > for windows and mapped it to FILE_FLAG_WRITE_THROUGH in
>>> > win32_open.c.
[snip]

> Michael Paesold wrote:
>>The original patch did not have any documentation. Have you
>>added some? Since this has to be configured in GUC (wal_sync_method),
>>the implications should be documented somewhere, no?

>The patch just implements behaviour that was already documented (for
>unix) on a new platform (win32). The documentation in general appears >to 
>have very little information on what to pick there, though ;-)

Reading your mails about the pull-the-plug tests, I see that at least with 
write caching enabled, fsync is more secure on win32 than open_sync. I.e. 
one should disable write caching for use with open_sync. Also open_sync 
seems to perform much better. All that information would be nice to have in 
the docs.

Best Regards,
Michael Paesold 


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