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From "Geir Magnusson Jr." <g...@pobox.com>
Subject Re: document insert rate
Date Sun, 04 Jan 2009 18:35:15 GMT
I'm suspicious.

On an m1.small instance running 32-bit ubuntu 8 on ec2 running trunk,  
I can get 85 inserts per second with the client running on same slice,  
so no network hop.  it's a single core instance, but I'm not sure that  
would matter too much (i'll try later).

Now, this makes me wonder... the fsync() in linux isn't doing what  
F_FILESYNC does in OS X presumably....  in which case what you think  
is being done for you to work around the lack of an "off switch"  in  
the erlang VM isn't actually being done, and since no one seems to  
have noticed, does it really matter? :)

To be fair, I'm going to try a better experiment on linux w/ more  
cores and more clients...

geir


On Jan 4, 2009, at 12:45 PM, Jan Lehnardt wrote:

>
> On 4 Jan 2009, at 14:09, Geir Magnusson Jr. wrote:
>>
>> 2) Is anyone using CouchDB in a manner that really requires this  
>> level of data security?  I appreciate having the *option* to turn  
>> on a mode like this, but I don't think I need it all the time.  I  
>> can use RAID systems that give me battery-backed cache, or I can  
>> make the design decision that I am happy to lose X seconds of data  
>> in a tradeoff (e.g. do the deep fnctl() every X seconds.....)
>
> Everybody. CouchDB doesn't have an `off`-switch. You just terminate
> the Erlang VM. Without this design, this wouldn't be possible. There
> has been no discussion about optionally making different trade-offs
> for speed and against data integrity, but this is not off-the-map.
>
> Cheers
> Jan
> --


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