>>> On Wed, Sep 26, 2007 at  7:29 PM, in message <[EMAIL PROTECTED]>,
"Florian G. Pflug" <[EMAIL PROTECTED]> wrote: 
> Kevin Grittner wrote:
>> I omitted the code I was originally considering to have it work against
>> files "in place" rather than as a filter.  It seemed much simpler this
>> way, we didn't actually have a use case for the additional functionality,
>> and it seemed safer as a filter.  Thoughts?
> A special "non-filter" mode could save some IO and diskspace by not actually 
> writing all those zeros, but instead just seek to SizeOfWal-1 after writing 
> the 
> last valid byte, and writing one more zero. Of course, if you're gonna
> compress the WAL anyway, there is no point...
Right.  And if you're not, why bother setting to zero?  I couldn't invent
a plausible scenario where we would want to do the update in place, and
I'm afraid someone might be tempted to run it against "live" WAL files.
So I decided it was best to let it lie unless someone else had a real-
life situation where it was useful.  Even then, I could write a bash
script to do it using the filter a lot faster than I could modify the C
code to safely deal with the files in-place, so I'm pretty skeptical.

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