Re: Page-at-a-time Locking Considerations

Tom Lane wrote:
> Zdenek Kotala <Zdenek.Kotala@Sun.COM> writes:
>> I tried to use memory mapped files (mmap) for clog and I think it should be also 
>> possible way. I got about 2% better performance, but it needs more testing.
> 
> If you only got 2% out of it, it's not even worth thinking about how to
> fix the serious bugs that approach would create (primarily, lack of
> control over when pages can get flushed to disk).

You can flush a pages by msync() function which writes dirty pages on 
disk. I don't see any other problem. Originally I tried to fix problem 
with a lot of parallel issues reported by Jignesh. However, it needs 
more testing if it really helps.
    Zdenek