Re: [REVIEW] Re: Compression of full-page-writes

On Wed, Dec 10, 2014 at 07:40:46PM +0530, Rahila Syed wrote:
> The tests ran for around 30 mins.Manual checkpoint was run before each test.
> 
> Compression   WAL generated    %compression    Latency-avg   CPU usage
> (seconds)                                          TPS              Latency
> stddev               
> 
> 
> on                  1531.4 MB          ~35 %                  7.351 ms     
>   user diff: 562.67s     system diff: 41.40s              135.96            
>   13.759 ms
> 
> 
> off                  2373.1 MB                                     6.781 ms    
>       user diff: 354.20s      system diff: 39.67s            147.40            
>   14.152 ms
> 
> The compression obtained is quite high close to 35 %.
> CPU usage at user level when compression is on is quite noticeably high as
> compared to that when compression is off. But gain in terms of reduction of WAL
> is also high.

I am sorry but I can't understand the above results due to wrapping. 
Are you saying compression was twice as slow?

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