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From H├ęctor Izquierdo Seliva <izquie...@strands.com>
Subject Re: Anyone using Facebook's flashcache?
Date Mon, 18 Jul 2011 10:14:51 GMT

> 
> Hector, some before/after numbers would be great if you can find them.  
> Thanks!
> 

I'll try and get some for you :)

> What happens when your cache gets trashed?  Do compactions and flushes 
> go slower?
> 

If you use flashcache-wt flushed and compacted sstables will go to the
cache. 

All reads are cached, so if you compact three sstables into one, you are
stuffing your cache with a lot of useless crap and evicting valid blocks
(flashcache won't honor any of the hints set with fadvise, as it's a
block cache layer and doesn't know of them anyway). If your write rate
is low it might work for you. 



> aj
> 
> >
> 



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